Trull, Timothy J., 1960-, author
Thomson , 2005
Buku Teks
Johana E. Prawitasari, author
Erlangga, 2011
Buku Teks
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