Artikel Jurnal
Beaty, Janice J., author
Kencana, 2013
Buku Teks
Pelligrini, Anthony D., author
Lawrence Elbaum Associates, 1996
Buku Teks
Beilharz, Peter, author
Pustaka Pelajar, 2005
Buku Teks
Rodriguez, Noelie, author
Sage Publications, 2001
Buku Teks