Bennett, Paul
Open University Press, 2003
Buku Teks
Page, James Daniel
Tata McGraw-Hill, 1994
Buku Teks
Comer, Ronald J.
W.H. Freeman, 1998
Multimedia
Nolen-Hoeksema, Susan
McGraw-Hill, 2007
Multimedia
Nolen-Hoeksema, Susan
McGraw-Hill, 2004
Buku Teks