McDonald, Ruth, author
Open University Press, 2002
Buku Teks
edited by Kathleen Kelly
Mosby, 1994
Buku Teks
Rapoport, John, author
An Aspen Publication, 1982
Buku Teks
McLean, Robert A., author
Delmar, 1997
Buku Teks
McLean, Robert A., author
Delmar, 2003
Buku Teks