D`Anieri, Paul, author
Wadsworth and Cengage Learning, 2012
Buku Teks
Leighton, Marian
St. Martin's Press, 1989
Buku Teks
Rourke, John T., author
McGraw-Hill, 2010
Buku Teks
Padelford, Norman J., author
Macmillan, 1962
Buku Teks
Rourke, John T., author
McGraw-Hill, 2001
Buku Teks