Coker, Cheryl A.
McGraw-Hill, 2004
Buku Teks
Utley, Andrea
Taylor and Francis, 2008
Buku Teks
Magill, Richard A.
McGraw-Hill, 2004
Buku Teks
Magill, Richard A.
McGraw-HIll, [Date of publication not identified]
Buku Teks
Magill, Richard A.
McGraw-Hill, 1998
Buku Teks