Denhardt, Robert B., author
Cengage Learning, 2015
Buku Teks
Gaus, John M., author
University of Alabama Press, 1055
Buku Teks
Shafritz, Jay M., author
Wadsworth/Thompson Learning, 2004
Buku Teks
Fesler, James W. (James William), 1911-2005, author
Prentice-Hall, 1980
Buku Teks
Berkley, George E., author
McGraw-Hill, 2009
Buku Teks