The International Association, 2004
Buku Teks
Matsumoto, David, author
Thomson Wadsworth, 2004
Buku Teks
The Guilford Press, 2007
Buku Teks
Young, Kimball
Kegan Paul, Trench, Trubner, 1946
Buku Teks
Young, Kimball, author
Trench, Trubner, 1946
Buku Referensi