Addison Wesley Publishing Company, 0
Buku Teks
Strommen, Ellen A., author
Dorsey Press, 1983
Buku Teks
Lucas, Bill, author
Nicholas Brealey Publishing, 2002
Buku Teks
Foley, Gerald, author
Yayasan Obor Indonesia , 1993
Buku Teks
Wallace, Harold R.
South-Western Educational, 1995
Buku Teks