For my refrence
Michael Schredl, Gerard Schäfer, Bettina Weber & Isabella Heuser, "Dreaming and Insomnia: Dream recall and dream content of patients with insomnia", Journal of Sleep Research, Vol. 7, 1998, pp.191-198

J. A. Cheyne, "Situational Factors Affecting Sleep Paralysis and Associated Hallucinations: position and timing effects", Journal of Sleep Research, Vol. 11(2), 2002, pp.169-177

E. J. O. Kompanje, "'The devil lay upon her and held her down' Hypnagogic hallucinations and sleep paralysis described by the Dutch physician Isbrand van Diemerbroeck (1609-1674) in 1664", Journal of Sleep Research, Vol. 17(4), 2008, pp.464-467

J. Allan Cheyne, Ian R. Newby-Clark and Steve D. Rueffer, "Relations among hypnagogic and hypnopompic experiences associated with sleep paralysis", Journal of Sleep Research, Vol. 8(4), 1999, pp.313-317

J. A. Cheyne, "Sleep paralysis episode frequency and number, types and structure of associated hallucinations", Journal of Sleep Research, Vol. 14(3), 2005, pp.319-324

Valérie Simard and Tore A. Nielsen, "Sleep paralysis-associated sensed presence as a possible manifestation of social anxiety", Dreaming, Vol. 15(4), 2005, pp.245-260