edited by Chris Cooper and Stephen Wanhill
John Wiley & Sons, 1997
Buku Teks
Kimmel, Allan J., author
Blackwell Publishing, 2007
Buku Teks
Black, James A., author
John Wiley & Sons, 1976
Buku Teks
edited by Shirley M. Stinson and Janet C. Kerr
Charles Press , 1986
Buku Teks
Anderson, James A., author
McGraw-Hill, 1987
Buku Teks