Buchanan, Robert Angus
Penguin, 1972
Buku Teks
Waldman, Don E.
Pearson, 2007
Buku Teks
Satterfield, Charles N.
Krieger, 1996
Buku Teks
edited by Lyle F. Albright, Billy L. Crynes, William H. Corcoran
Academic Press, 1983
Buku Teks
Satterfield, Charles N.
McGraw-Hill , 1991
Buku Teks