Horman, Hans
Wissenschaftliche Buchgesellschaft, 1981
Buku Teks
Mooij, Antoine Willem Michiel
Boom Meppel, 1975
Buku Teks
Slama-Cazacu, Tatiana
The Hague Mouton, 1973
Buku Teks
Psychology Press, 2000
Buku Teks
Field, John, author
Routledge, 2005
Buku Teks