Willes, John H.
McGraw-Hill, 2005
Buku Teks
Stephan, Paul B.
Charlottesville, 1996
Buku Teks
Cheeseman, Henry R.
Prentice-Hall, 1998
Buku Teks
Park, William W.
Oxford University Press, 2012
Buku Teks
edited by Dennis Campbell
Graham & Trotman, 1990
Buku Referensi