Willborn, Steven L.
The Michie Company, 1993
Buku Teks
Hacker, Andrew
McGraw-Hill, 1973
Buku Teks
Nannes, Caspar H,
The Catholic University, 1960
Buku Teks
Field, Oliver P
Harper, 1949
Buku Teks
Patterson, Thomas E., author
McGraw-Hill, 203
Buku Teks