Rowlan, Donald T.
Springer, 2012
eBooks
Welfel, Elizabeth Reynolds, author
Brooks/Cole Cengage Learning, 2013
Buku Teks
edited by Kathleen J. Bieschke, Ruperto M. Perez, Kurt A. DeBord
American Psychological Association, 2007
Buku Referensi
Sommers-Flanagan, John, author
John Wiley & Sons, 2012
Buku Teks
Corey, Gerald, author
Refika Aditama , 2003
Buku Teks