Fagen, Richard R.
Calif Standford University Press, 1969.
Buku Teks
Fagen, Richard
Blackwell, 1987
Buku Teks
Department of State, 1961
Buku Teks
edited by Lucian W. Pye and Sidney Verba
Princeton University Press , 1965
Buku Teks
edited by Andrew Blasko, Diana Januauskiene
Council for Research in Values and Philosophy, 2008
Buku Teks