Duffy, Karen G., author
Pearson Education, Inc., 2005
Buku Teks
Duffy, Karen G., author
New Jersey, 2005
Buku Teks
edited by Gordon H. Bower
Random House, 1987
Buku Teks
by Richard R. Bootzin [and others]
Mcgraw-Hill , 1991
Buku Teks
Hoffman, Lois, author
McGraw-Hill, 1994
Buku Teks