Terry, George Robert, author
Prentice-Hall, 1957
Buku Teks
Waveland Press, 1979
Buku Teks
Kerin, Roger A., author
Prentice Hall international, 2001
Buku Teks
Smykey, Edward W., author
Macmillan, 1961
Buku Teks
Evans, Joel R.
Macmillan, 1985
Buku Teks