Moore, Gary A., author
South-western Publishing, 1987
Buku Teks
Twomey, David P., author
Thomson Learning, 2002
Buku Teks
Cheeseman, Henry R., author
Pearson/Prentice Hall, 2007
Buku Teks
Mueller, Rudolf, author
Fritz Knapp Verlag, 1972
Buku Teks
Moore, Gary A., author
South-Western Publishing, 1987
Buku Teks