Boyd, Denise, author
Pearson, 2005
Buku Teks
Turner, Jeffrey S., author
Holt, Rinehart and Winston, 1987
Buku Teks
Turner, Jeffrey S., author
Harcourt Brace College, 1995
Buku Teks
Berk, Laura E., author
Allyn and bocon , 2001
Buku Teks
Dacey, John S., author
McGraw-Hill, 2002
Buku Teks