Niemi, Richard G., author
Jossey-Bass, 1974
Buku Teks
Merriam, Robert E. (Robert Edward), 1918-, author
Harper & Brothers, 1957
Buku Teks
Kegley, Charles W. (Charles William), Jr., author
Wardsworth, 2010
Buku Teks
edited by Harry Eckstein and David E. Apter
Free Press, 1968
Buku Teks
Richardson, Bradley M., author
Harper Collins, 1984
Buku Teks