McDonald, Ralph E.
Mosby , 1987
Buku Teks
edited by Carolyn Uhlinger Shantz and Wiliard W. Hartup
Cambridge , 1995
Buku Teks
Pressley, Michael
Guilford Press, 2007
Buku Teks
Wicks-Nelson, Rita
Pearson Education, 2014
Buku Teks
edited by Joseph D. Noshpitz
John Wiley & Sons, 1997
Buku Referensi