Tijdschrift voor parapsychologie.
Gewijd aan de studie van het occultisme in zijn vollen omvang / Orgaan van de Studievereniging voor Psychical Research.
1928--1981? Bimonthly, quarterly
Amsterdam, then Utrecht, then Den Haag, Netherlands.
Language: Dutch.
Publisher: SPR (Utrecht); H.P. Leopold (Den Haag).
Editor: P.A. Dietz, W.H.C. Tenhaeff; H.A.C. Denier van der Gon, C.H. van Os, D.H. Prins; Dick J. Bierman.
Succeeds: Mededeelingen van de Studievereniging voor Psychical Research / Parapsychologische nieuwsbrief
Corporate author: Studievereeniging voor Psychical Research; Parapsychology Institute
1/1, November 1928-1981. 48 pp. Suspended 1942-1945, f 5.50 a year, f 6.0- abroad.

Tenhaeff (1891-1981), who was the first professor of parapsychology in the world (at Utrecht) was the initial impetus for this journal with P.A. Dietz. It was the principal Dutch-language journal of psychical research and its reputation was tarnished by the exposure of Tenhaeff in the late 1970s for falsification of data in connection with the testing and promotion of the psychic Gerard Croiset (1909-1980).