New York University Press, 1979
Buku Teks
Pierre, Andrew J., author
Princeton University Press, 1982
Buku Teks
George-Braziller , 1963
Buku Teks
Halle, Louis
Harper & Brothers,, 1959
Buku Teks
Spindler, J. Andrew
Brookings Institution, 1984
Buku Teks