Ghost Explained (Part 4)

Plasma and Psychospheres

by Marinus Anthony van der Sluijs

A Field Phenomenon

Perhaps one of the most intriguing mysteries to make it into the 21st century without ever having been resolved is the ghost phenomenon.[1] Such a vast literature has been written on the subject that I will not expound on anything in this brief paper, but straightforwardly introduce a possible working hypothesis that may guide us in future investigations.

In every ghost apparition essentially two participants can be identified:

• the percipient is the one and sometimes the group undergoing the experience;
• the agent is the ghost itself or the person who is represented by the ghost, himself often deceased.

The most fundamental issue at stake in the ghost phenomenon appears to be the question who or what triggers the apparition: who takes the initiative? Subjective theories argue that the percipient himself initiates the apparition, for example as the effect of his unconscious on his sensory organs. Objective theories, on the other hand, advocate the view that there really is physical substance and actuality in the apparition, in other words, that the ghost itself may really operate on the percipient.[2]

Taking all the evidence together it would seem that there are certain arguments in favour of both explanations. Given the strong neurological resemblance between ghost apparitions and hallucinations, for example, it sounds likely to assume that the ghost apparition is essentially a between-the-ears process. Yet other considerations vouch for the physical existence of the ghost:

• the ghost is frequently observed by more than one person, all in their right minds, and appears to each of them in the correct perspective;
• the percipient generally does not even remotely expect to see anything of the kind, as most ghosts come completely ‘out of the blue’;
• many percipients have skeptical views of the paranormal and are greatly surprised by what they see;
• the ghost often appears opaque, blotting out objects behind it;
• the ghost is sometimes reflected in a mirror;
• the ghost often looks exactly like the agent, wearing clothes or having physical characteristics that are by no means known to the observer;
• the ghost is occasionally seen by animals as well, who sometimes even point the apparition out to the human percipient.

Thus, on one hand there is no denying that the ghost apparition is connected with hallucinatory processes in the brain,[3] whilst on the other hand there really appears to be some sort of external trigger. It seems warranted, then, to assume in the final analysis that both objective and subjective explanations play a part in the process. Now, how could this be envisioned?

I think a theory of ghosts could greatly benefit from the use of a field model. Field theory is especially common in physics, where it is used to account for the simultaneous presence or operation of certain forces in different places at the same time. The best known fields are the gravitational and the electromagnetic fields. Fields have a number of basic properties which will turn out to be of great help in a theory of ghosts:

#1. A field is typically generated by a single object.

#2. Fields can only be felt or experienced if you are properly attuned to them.

#3. Two or more different fields can overlap if they are close enough or the spheres are large enough. The resulting force in the overlapping area will be the sum of the forces of the overlapping fields.

#4. The field radiates outwards from this objects with a gradual decline in strength. The strength of the field declines in space and time – in space, because the further you are removed from the centre the weaker the field becomes, and in time, because the longer after the original generation of the field, the weaker the field becomes.

These characteristics seem to make sense of many aspects commonly involved in ghost experiences:

#1. A large class of ghost apparitions, most notably the deathbed and near-death apparitions and so-called crisis apparitions, take place on occasion of extreme emotional stress, usually of a negative kind, but occasionally of a delightful nature. It would seem, then, that the psychological crisis experienced by the agent generates a field of some kind, which forms the basis of the apparition. I will provisionally call this field a psychic field or a psychosphere.[4]

#2. Many people never see ghosts and it even occurs that some people in a group see it, but one in the group misses it. There appears to be a selection of people who can observe a ghost. This could be explained by a field model, in which persons whose senses pick up the right wavelengths can see a ghost. This notion bears a close resemblance to Rupert Sheldrake’s suggestion of morphic fields, which convey information relevant to select groups of individuals, as well as to theories of telepathy. As a rule of thumb you could say that people who are closely related or know each other well seem to be better ‘tuned in’ to each other and that might help explain why so many ghosts are identified as family members of the percipient, dead or alive.[5]

#3. The discrepancy between the objective and subjective theories of ghosts could now be overcome by invoking the principle of an overlap of fields. If we might posit for the moment that every human being – or every animal with a brain – has his own psychosphere, then all types of non-verbal, non-visual and distant communication could be understood as the result of an overlap of psychospheres,[6] facilitated if the persons involved are tuned in to the same wavelengths. Thus, if someone sees a ghost it is neither enough to suppose that the agent is sending out signals nor to suppose that the percipient is hallucinating, but both are true at once, as it is a mutual process triggered by this overlap of psychospheres. The agent, typically on occasion of crisis, broadcasts strong signals constituting his own psychosphere, which are picked up by the percipient if he is tuned in properly.[7] The psychosphere must somehow be supposed to convey all the necessary information to ‘make a ghost’ and ‘deliver a message’, for which issue see below.

#4. The gradual decline of a field in time and space works well for the ghost phenomenon. Naturally, you would expect that the psychosphere is at its strongest close to the agent and at the moment of the crisis itself. This is, of course, why deathbed apparitions are such a common class of ghost observations. The two other dominant classes of ghost apparitions are haunters and crisis apparitions. Haunters and to a lesser degree revenants are classes of ghosts who are bound to one particular place and appear more than once in that area for an extended period of time. Many people can see the same haunters, including people who have no idea who the haunter is. Unlike haunters, crisis apparitions are ghosts who are seen in a different place than the place of trauma, often far removed from it, but this time almost exclusively by close relatives and friends of the agent. Thus, haunters and crisis apparitions appear to be each other’s opposites in terms of distance and familiarity:

location: seen by:
haunters: same place anyone
crisis apparitions: anywhere close family and friends

These observations receive an excellent explanation in terms of a field, as the two classes of ghost apparitions correspond to the peaks of field strength in space and time respectively. That is, whilst the field strength gradually declines after the crisis it can still be picked up either by being close to the centre of the field, where it was generated (haunters) or by being well attuned to the correct wavelength (crisis apparitions). If you are far removed from the source and are not tuned in to the particular person you will miss the signals.

This explanation requires, almost as a corollary, that a psychosphere imprinted by someone in mental crisis can linger on after the person’s death. This imprint could then be identified with a ‘soul’ or ‘astral double’, if you like.[8] It supposedly forms a double of the agent in crisis himself and sometimes even of his environment.

What Type of Field?

The upshot is that a field theory of some sort would seem able to make sense of the communication aspect of the ghost experience. The next step from here would be to determine what type of field this is and how exactly it can convey information about the form, the behaviour and the message of the ghost. In the large majority of cases the ghost turns out to look exactly like the agent, often displaying features of which the percipient was by no means aware. Does the field somehow contain a three-dimensional image of a visual type, so that the percipient’s brain, receiving these data turns them into a hallucinatory vision, giving the percipient the feeling that he has actually observed the ghost with his eyes and other senses?[9]

A first step towards the answer is to remember that the human brain and nervous system are of an electric nature.[10] The impulses sent from our eyes, ears, nose and skin to our brain are electrical signals transported through our nerves. Thus, the information constituting a ghost experience always ends up in an electric format in our brains, but if we want to find out whether the ghost is merely a set of field parameters picked up by our brain or a real observed object, we need to know if the psychosphere itself could be an electromagnetic field. Now, interestingly, there are telling clues that ghosts do indeed have a close connection with electromagnetic phenomena:

A neighbour boy enlisted to the Marines, and was serving in the Pacific. His parents heard nothing for about six weeks, his mother was wild with anxiety. One morning I stood looking across our yard toward our neighbor’s mailbox thinking ‘If only Bob’s mother could get a letter’. As if in answer to my prayer, there stood Bob, right near the mailbox, in his Marine uniform. He and his uniform appeared pale in colour and fuzzy in outline. He neither moved nor spoke … After Bob stood there for a minute or two impressing his thought on my mind, his ‘body’ started to rise. It stretched out longer and thinner – not straight into the sky, but at an angle of perhaps 30 degrees from the vertical. When the head and shoulders were perhaps 3 metres above where they had been at first they suddenly turned into (or went into) a bright shaft of light, like a very bright electrical bolt. The balance of the figure followed the head and shoulders into the light and disappeared. The bolt appeared about a metre long and 12 centimetres in diameter. The queer thing was the sparks of blue and green light that appeared to radiate from the lower edge of the bolt, and the yellow and red sparks that came from the upper end … Bob’s last two letters came that day, and in September came a ‘missing in action’ telegram.[11]

Filmed for a television documentary, investigators headed by William Roll and Andrew Nichols, both of them professors of parapsychology in American universities, found significant electromagnetic readings in houses where hauntings were claimed.[12]

Eastman, Chief Engineer at the Rhodes Electrical Company, London, was working with his colleague Harold Woodew in a darkened room, arranging high-tension wires to form a magnetic field. To their astonishment, a luminous blue sphere began to form over a dynamo revolving near them. Then, as the light grew brighter, they saw a form resembling a human hand appear in the centre of the sphere. They watched it for several minutes, until it faded away. For four days, the two men worked to re-create the conditions in which the phenomenon had occurred. When they eventually succeeded, the sphere again appeared, but this time the form which appeared in the magnetic field resembled a human head, white in colour and slowly revolving.[13]

During an apparition the percipient’s hair is often raised and the person frequently feels a chilling passing wind as well:

Percipients quite often tell us they have a feeling of something strange before they actually see their ghost … At one point during the Cheltenham case, Rosina Despard notes, ‘I felt a cold icy shiver’ when the ghost bends over her while she is playing the piano. On another occasion five of the witnesses feel ‘a cold wind, though their candles were not blown about’.[14]

Ghosts sometimes produce Poltergeist effects, such as lifting tables, or closing windows or doors. These observations could be explained in terms of electromagnetism as well.

It would seem, then, that the psychosphere is an electromagnetic field or at least has an influence on electromagnetism. But how could an electromagnetic field possibly take on the visual appearance of a ghost? This question has to my knowledge never been answered in existing literature and it is at this point that I would like to introduce plasma as the possible key to decipherment of the ghost enigma.[15] A plasma is an ionised gas, which is by definition located in an electromagnetic field. The particles of the plasma rearrange themselves according to the field lines of the magnetic field, so that a plasma in a field with a sufficiently strong current becomes a visible manifestation of the magnetic field. The shape a plasma takes on, therefore, is the shape of the magnetic field. It is now generally acknowledged that plasma accounts for 99.9 % of the universe; well-known examples of plasma formations are stars, the sun, the auroras, lightning, and fire. I would now propose the following working hypothesis for a new theory of ghosts:

A ghost is a plasma formed when the percipient’s electromagnetic field overlaps with the electromagnetic ‘psychosphere’ of the – often distant – agent and the combined field strength ionises the gas particles in the air.

This hypothesis could be tested by a detailed comparison of the morphology of ghosts with plasma physics. Although I am in no way a specialist in plasma physics, a general reading of literature would support the following observations:

• Ghosts often glow or are visible in the dark. This is a property of plasma.
• Ghosts run the gamut of sometimes being completely transparent and sometimes being completely opaque. Opacity is a function of the density of the plasma.
• Ghosts occasionally produce sound, but they often have difficulty with it, fail to say something, or merely utter an eerie cry. Plasmas, such as auroras and lightings, are frequently accompanied by sound.
• Most ghosts are stationary, but some are engaged in some activity or move around. Plasmas could be either stationary or mobile.
• Ghosts are sometimes seen passing through walls, but often open doors like ordinary people. There would be no boundaries for moving plasmas, although it appears that the agent urges the plasma to react as a living person would do.
• Ghosts never leave physical objects behind. Plasmas are simply ionised gases.
• Many ghosts start off as a ball, then become a ring or a humanoid form. Witness the following examples:

A party of young people and myself determined on All Hallow’s Eve to play at the childish game of sitting separately in dark rooms, with supper laid for two, with the intention of awaiting the appearance of a future husband or wife. Thinking the whole thing a joke, and not in the least expecting to see anything, I distinctly saw, first, a flimsy cloud which rose up at the other end of the room, then the head and shoulders of a man, middle-aged, stout, with iron-grey hair and blue eyes – not in the least the picture which a young girl would imagine she saw on such an occasion.[16]

Frau Schmidt-Falk is climbing alone, when she happens to miss her way: ‘… Having started a little late for the return, and light beginning to fade, all of a sudden I found myself in a really dangerous position … All of a sudden I noticed a sort of a big ball of light, and this condensed to the shape of a tall, rather Chinese looking gentleman … The gentleman bowed, spoke a few words, led me a small path to the tourists’ way, and disappeared as a ball of light.[17]

When we were about five, Aunt Sarah died … About two weeks later, Bud and I were playing by the side of the house at twilight (sic!). I happened to look up and saw a cloudy, swirling vapour. It became Aunt Sarah, standing there by the house.[18]

(While working with medium Marthe Béraud) ‘I see something like a white vapour, about 40 centimetres from me. It is like a white veil or handkerchief on the ground. This whiteness rises, becomes rounded. Soon it is a head, level with the ground: it rises further, grows, and becomes a human figure, a short man, wearing a turban and a white robe, with a beard …[19]

I was lying on a divan, reading, at about 5 p. m., when I saw at the doorway a little luminous circle, like the reflection of a mirror. I could see nothing that would cause such a light. The luminous circle became larger, and when it was as big as the door itself, a kind of dark shadow appeared in the middle of it. A human figure formed more and more distinctly, then detached itself from the wall and advanced towards me.[20]

Other than the visible plasma, the intruding psychosphere might contain additional electromagnetic information to be read by the brain of the percipient, which could perhaps account for the missing information, important advice, correct hiding place and so forth transmitted by the ghost in many ghost experiences. Needless to say that the investigation has only just begun.

Appendix

The following is a very brief extract of the findings of Hilary Evans’ detailed study of ghost apparitions:

Types of ghosts[21]

#1 from the past:
#1a revenants
#1b deathbed and near-death
#1c haunters
#2 of the present:
#2a crisis apparitions
#2b living ghosts
#2c autophany and bi-location
#3 of the future
#4 out of time:
#4a aerial battles and other events
#4b archetypal ghosts

Characteristics of ghosts[22]

#1 a ghost is generally life-like in appearance;
#2 a ghost is usually ‘seen’ in much the same way as if it was real;
#3 a ghost may be seen either collectively or selectively;
#4 a ghost may change its appearance during the sighting;
#5 a ghost generally adapts to its surroundings (by minding doors and so on)
#6 a ghost may appear by forming from a luminous or misty shape;
#7 a ghost is generally dressed naturally … but sometimes not;
#8 a ghost may be clearly defined … or fuzzy;
#9 a ghost may be seen in whole or in part;
#10 a ghost’s appearance may contain details unknown to the percipient;
#11 a ghost may be opaque or transparent, may reflect or not, cast a shadow or not;
#12 a ghost may or may not be seen by its own luminosity;
#13 ghosts can make sounds;
#14 a ghost may perform a physical action … but if so, the action is trivial;
#15 a ghost may be touched and felt … but lack material substance;
#16 a ghost may respond to the percipient or act as though s/he isn’t there;
#17 a ghost generally makes a once-only visit … but sometimes returns;
#18 a ghost may appear in two places simultaneously, or within an impossibly short space of time;
#19 a ghost may depart naturally, or vanish abruptly, or simply fade away;
#20 a ghost never leaves any souvenir, memento or trace;
#21 a ghost may be seen by the ‘wrong’ person;
#22 a ghost frequently fails to establish its identity;
#23 ghosts are frequently sensed.

Purposes of the ghost experience[23]

#1 apparitions offering comfort, counsel, help
#2 apparitions requesting comfort, counsel, help
#3 apparitions warning of danger
#4 apparitions seeking to complete ‘unfinished business’
#5 apparitions manifesting malevolence
#6 apparitions as messengers of doom.

Marginally related phenomena[24]

#1 dreams
#2 hallucinations
#3 religious visions
#4 battlefield helpers
#5 folklore entities
#6 angels and women in white
#7 demons and men in black
#8 bedroom visitors
#9 extraterrestrial beings
#10 séance-room materialisations

Those who have the ghost experience[25]

#1 exceptional people
#2 sensitive people
#3 ‘encounter-prone’ people
#4 exceptional states
#5 mystical states
#6 exceptional circumstances
#7 violent death and reincarnation
#8 immediate circumstances
#9 geophysical parameters.

So, if a person experiences a severe electric shock, or his house is built on clay, or he is susceptible to thunderstorms, or he is laid low by fever, or eats the wrong food or no food, or dallies with drugs or abuses alcoholic beverages, or pushes himself too hard at the office, or drives alone at night or sails alone across an ocean, or undergoes a spiritual transformation or quarrels with his partner at the breakfast table – in these or a hundred other situations, he may be rendered more likely to have a ghost experience.[26]

Conclusions

• Because we know that the subconscious … can visualize a hallucination, we may accept this as the process whereby an apparition is perceived, the suggestion either originating in the individual’s own subconscious, or suggested to it by an external agent.

• Because we know no limits to the creativity of the human mind, we may accept the possibility that many ghosts … are visualizations, exteriorized by the percipient’s own subconscious and accepted as real by his conscious mind.

• Because we know that the mind is occasionally capable of remote viewing we know that psi exists, and because the mind can be capable of precognition, we know that super-psi exists; and because we know no limits to super-psi, we may conceive it possible that the mind can obtain unlimited access to information of every kind.

• Because we know that projection takes place, we know that the extended self, or something like it, must exist. If so, it is a likely candidate for many types of apparition, notably living ghosts and those which seem to involve bi-location.

• Because the extended self, in the course of projections, displays memory, awareness and other indications of intelligence … we may accept that these faculties can exist apart from the physical body.

• Because the extended self, possessing awareness, intelligence and memory, can seemingly exist apart from the physical body, we may further conceive that it could survive the death of the physical body, and even continue to display signs of individual personality.

• Because we know that ghosts sometimes communicate information known to no living person, and utter veridical warnings, we know that whatever causes them enjoys seemingly unlimited access to knowledge; this could be the percipient’s own subconscious, or the extended self of the surviving dead, using super-psi.

• Because there are cases in which more than one person sees the same ghost in natural perspective, we may conceive that the subconscious, or the extended self, or the two in collaboration, can create a short-lived apparition which has some degree of material substance.[27]

References

[1] Along with a host of closely related phenomena such as UFOs, saintly visions, battlefield helpers, folklore entities, angels, demons, women in white and men in black, extraterrestrial visitors, séance-room materialisations, and bedroom visitors, see H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 130-165

[2] Compare: We have basically two models for the experience: • The subjective model, originating with the subconscious of the percipient. Either of its own accord, or in response to information obtained via psi or super-psi – comprising telepathy, clairvoyance, and unlimited access to information including precognition and retrocognition – the subconscious initiates a visualization process whereby it exteriorizes an image which can be perceived consciously by the percipient, and perhaps by others, as an apparition. • The external model, originating with an external agent – by which we generally mean the extended self of a person still living, or the surviving extended self of a person once living but now dead – which is able either to manifest as an apparition, or to impose an image by suggestion on to the subconscious of the percipient(s) and cause it to exteriorize an apparition … in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 235f.

[3] Compare: Psychological variables of many kinds are the building blocks of the ghost experience: hallucination is no more than the process which enables them to find visual expression as the devil, an extraterrestrial alien or Aunt Jane’s ghost, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 137

[4] William Roll calls this a psi field: Because the ‘telepathic charge’ of a haunted house is similar to the magnetic, gravitational, and other fields that surround physical objects, I have used the concept of psi field to describe psi phenomena that seem to depend on such objects. We can think of the psi field of an object, whether animate or inanimate, as a pattern of associations … In the same way as a magnet may magnetize another piece of metal and then be destroyed without affecting the new magnet, so may the images, ideas, and so on of a person continue to exist as part of the psi fields of objects with which he was once in contact, after he has gone. The image of a person seen in an apparition, whether this image was produced by him or someone else, may survive his death without being inhabited by his consciousness, William Roll, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 250

[5] James Crenshaw has toyed extensively with the idea of different realities with different wavelengths, as the following quotes show: Aside from the considerations of pure spirit, the same kind of vibrating energy, the same kind of dancing wave patterns that we encounter here are to be found there. Only the wavelengths, the incredibly rapid rate of vibration – frequencies of high orders unimagined in our world – appear to be different, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 271. The residents of the next world are able to take on a lower frequency, allowing them to manifest in our space and time. This is like a different radio or TV frequency, to which you need to be attuned if you are to receive the signal, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 271

[6] Compare: What happens when a witness perceives a haunter, in Price’s view, is that there takes place an ‘overlapping or interpenetration of two psychic atmospheres, the one which surrounds the percipient’s body and the one which pervades the room’ (which he supposes has been, as it were, left behind by the haunter after her death), in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 232

[7] Compare: One way of accounting for the crisis apparition would be if our subconscious is continually scanning the cosmos, like the radar scanner at an airfield, and picks up on happenings relevant to itself …, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 233

[8] Adolphe d’Assier in 1887 deemed this the ‘post-sepulchral spectre’: It is the phantasmal replica of all the organs of the human body. It has been seen, in fact, to move, speak, take nourishment, accomplish, in a word, the different functions of animal life. The molecules which constitute it are evidently borrowed from the organism which gave it birth. It may then be defined as a gaseous tissue offering a certain resistance, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 258

[9] This view is defended by Hilary Evans: It is attractive to suppose that the subconscious of some percipients – those that are, as it were, on the same wavelength as the psi field – may pick up a message from the psi field and externalize it as an apparition, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 250

[10] Compare: Like any brain process, hallucinations are essentially electrical; so in principle they can be recorded, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 142

[11] Pearl Ullrich, Bellingham, Washington State, 3 July 1944, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 88f.

[12] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 187

[13] Eastman, Woodew, London, circa 1930?, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 188

[14] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 92

[15] James Crenshaw’s theories came very close, but James had apparently never heard of plasma. He postulates fields of force as the basic building blocks of the universe: the particles which make up reality as we know it are merely ‘evanescent indicators’ of the emergence of these fields of force into our physical world of space and time. It is these fields which control the kind of growth and development exemplified by, say, the directive process of cell division, and – I suppose – the whole forward-progressing course of evolution. Crenshaw suggests that similar processes may result in apparitions and materializations: ‘the apparition appears to be made up of the same kind of transitory, emerging matter. It appears and disappears, can sometimes be seen and felt before disappearing, occasionally moves objects and leaves material traces …’ in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 270

[16] Mrs Gordon Jones, Anerley, England, Autumn, 1881, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 70

[17] Elsa Schmidt-Falk, Bavarian Alps, 1950s, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 109f.

[18] De Leon, Bonham, Texas, 1889, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 127

[19] Charles Richet, Villa Carmen, France, 1904, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 163

[20] N. Heintze, Moscow, Russia, 15 April 1884, in H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 163

[21] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 13-57

[22] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 58-94

[23] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 105

[24] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 130-165

[25] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 192-214

[26] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 213

[27] H. Evans, Seeing ghosts; experiences of the paranormal, John Murray, London, 2002: 273