Ravishankar, Sri Sri
Butir mutiara dari Sri Sri
2003
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Bentine, Michael
The door marked summer
Granada , 1981
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Research in parapsychology 1989: abstracts and papers from the thirty-second annual convention of the Parapsychological Association, 1989
editors, Linda A. Henkel, John Palmer
The Scarecrow Press, Inc., 1990
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Karolyi, George
An excursion into the paranormal
The Paranormal Phenomena Research Foundation, 2009
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Brooks, Fowler D.
The psychology of adolescence
Houghton Mifflin, 1929
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