Fessenden, Ralph J., author
Willard Grant Press, 1979
Buku Teks
Bruice, Paula Yurkanis, author
Upper Saddle River, 2001
Buku Teks
Boxer, Robert J., author
McGraw-Hill, 1998
Buku Referensi
Morrison, Robert Thornton, author
Prentice-Hall, 1992
Buku Teks
Morrison, Robert Thornton, author
Allyn and Bacon, 1973
Buku Teks