Madura, Jeff
South-Western College, 2001
Buku Teks
Cunningham, William H.
South-Western, 1984
Buku Teks
Pride, William M.
South Western Cengage Learning, 2012
Buku Teks
Glos, Raymond E.
South-Western Publishing, 1947
Buku Teks
Jucius, Michael J.
Richard D. Irwin, 1961
Buku Teks