Parker, Harry, author
John Wiley & Sons, 1984
Buku Teks
Shaeffer, R.E., author
Prentice-Hall, 2001
Buku Teks
Lauer, Kenneth R.
McGraw-Hill, 1981
Buku Teks
Ambrose, James E., author
John Wiley & Sons, 2005
Buku Teks
edited by Edwin H. Gaylord, Charles N. Gaylord
McGraw-Hill, 1968
Buku Referensi