Irish, Marian D.
Prentice-Hall, 1962
Buku Teks
by William J. Keefe ... [and others]
The Dorsey Press, 1983
Buku Teks
McKenna, George
McGraw-Hill, 1998
Buku Teks
Dye, Thomas R.
Harcourt Brace College, 2000
Buku Teks
Dye, Thomas R.
Thomson, 2006
Buku Teks