^ LeCron, Leslie; Bordeaux, Jean (1970). Hypnotism Today. Wilshire Book Co. p. 278. ISBN 0-87980-081-X. When in a trance ... the medium seems to come under the control of another personality, purportedly the spirit of a departed soul, and a genuine medium undoubtedly believes the 'control' to be a spirit entity ... In the trance, the medium often enters a cataleptic state marked by extreme rigidity. The control then takes over, the voice may change completely ... and the supposed spirit answers the questions of the sitter, telling of things 'on the other plane' and gives messages from those who have 'passed over.' https://drive.google.com/file/d/19XBpCeNfCJAhAffoBmEKrOMPHlCPQ1uy/view?usp=sharing
In 1970 two psychical researchers investigated the direct-voice medium Leslie Flint and found that all the "spirit" voices in his séance sounded exactly like himself and attributed his mediumship to "second-rate ventriloquism". The medium Arthur Ford died leaving specific instructions that all of his files should be burned. In 1971 after his death, psychical researchers discovered his files but instead of burning them they were examined and discovered to be filled with obituaries, newspaper articles and other information, which enabled Ford to research his séance sitters backgrounds.
^ "Glossary of Key Words Frequently Used in Parapsychology" Archived 2010-12-24 at the Wayback Machine, Parapsychological Association website. "Materialization: A phenomenon of physical mediumship in which living entities or inanimate objects are caused to take form, sometimes from ectoplasm." Retrieved January 24, 2006 "Medium – Definition". Dictionary.com. Retrieved 23 March 2007.