Plischke, Elmer
American Enterprise Institute for Public Policy Research, 1977
Buku Teks
Organski, A.F.K., author
Alfred A. Knopf, 1969
Buku Teks
edited by Andrew Gyorgy and Hubert S. Gibbs
Prentice-Hall, 1955
Buku Teks
edited by Roy C. Macridis
Prentice-Hall, 1959
Buku Teks
edited by Roy C. Macridis
Prentice-Hall, 1967
Buku Teks