Litterer, Joseph August, 1926-
John Wiley & Sons, 1973
Buku Teks
Pfifner, John M.
Prentice-Hall, 1960
Buku Teks
Jay M. Shafritz, J. Steven Ott, editor
Harcourt College, 2001
Buku Teks
edited by Jay M. Shafritz, J. Steven Ott
Wadsworth, 2005
Buku Teks
editedby Jay M. Shafritz, J. Steven Ott
Brooks/Cole, 1991
Buku Teks