American Psychological Assosiation, 2007
Majalah, Jurnal, Buletin
Tristiadi Ardi Ardani
Graha Ilmu, 2007
Buku Teks
Suprapti Slamet I.S., author
UI-Press, 2005
Buku Teks
Suprapti Slamet I.S., author
Penerbit Universitas Indonesia (UI-Press), 2008
Buku Teks
Richards, Thomas William
McGraw-Hill, 1946
Buku Teks