Healy, Karen
Palgrave Macmillan, 2005
Buku Teks
Martin, Ruben
Learning Matters, 2010
Buku Teks
edited by Jerrold R. Brandell
Free Press, 1997
Buku Teks
O`Sullivan, Terence
Macmillan, 1999
Buku Teks
Miley, Karla Krogsrud, 1942-
Pearson, 2014
Buku Teks