Bruice, Paula Yurkanis, author
Upper Saddle River, 2001
Buku Teks
Barret, Richard L., author
Charles E. Merril, 1965
Buku Teks
Henrickson, Charles, author
McGraw Hil , 2011
Buku Teks
Corwin, Charles H., author
Prentice-Hall, 2001
Buku Teks
Nicol, Malcolm F., author
Holden-Day, 1973
Buku Teks