Mash, Eric J., author
Thomson Wadsworth, 2005
Buku Teks
editor-in-chief Richard M. Lenrner
New Jersey Wiley, 2015
Buku Referensi
Ribble, Margaret A.
Columbia University, 1958
Buku Teks
Elias, Maurice J., author
Kaifa , 2003
Buku Teks
Santrock, John W., author
Erlangga, 2007
Buku Teks