McKillup, Steve, author
Cambridge University Press, 2011
Buku Teks
Kviz, Frederick J.
Litle, Brown & Co, 1980
Buku Teks
McClave, James T., author
Dellen Publishing, 1979
Buku Teks
Hays, William L., author
Harcourt Brace Colege, 1994
Buku Teks
McClave, James T., author
Dellen Publishing, 1985
Buku Teks