by Collin J. Watson [and others]
Allyn and Bacon, 1993
Buku Teks
Gwartney, James D.
FL. The Dryden Press, 1995
Buku Teks
Gwartney, James D.
Harcourt Brace Jovanovich, Publisher, 1987
Buku Teks
Kahn, Alfred E.
John Wiley & Sons Inc, 1995
Buku Teks
Gwartney, James D.
Harcourt Brace Jovanovich, Pub., 1990
Buku Teks