Santrock, John W., author
McGraw-Hill, 2009
Buku Teks
Crain, William C, author
Prentice-Hall, 2005
Buku Teks
Nadelman, Lorraine, author
Lawrence Erlbaum, 2004
Buku Teks
Singer, Hans W. (Hans Wolfgang), author
United Nations, 1972
Buku Teks
Smith, Peter K., author
Wiley, 2011
Buku Teks