edited by Pieter J.D. Drenth, Joseph A. Sergeant, Roelf J. Takens
John Wiley & Sons, 1990
Buku Teks
Haanel, Charles F, author
Mind Power Corporation, 2006
Buku Teks
American Psychological Association, Inc.,, 2018
Majalah, Jurnal, Buletin
Lahey, Benjamin B., author
2002
Multimedia
American Psychological Assosiation, 2001
Majalah, Jurnal, Buletin