Philadelphia : Open University Press, 2002,
Buku Teks
McMurray, Anne, author
Mosby , 2003
Buku Teks
Naidoo, Jenniem], author
Bailliere Tindal Elsevier, 2011
Buku Teks
edited by Jenny Douglas
Sage, 2007
Buku Teks
edited by Philip E. Sartwell
Appleton Century Crofts, 1973
Buku Teks