edited by H.S.W. Massey, E.W. McDaniel, Benjamin Bederson
Academic Press, 1982
Buku Teks
edited by Martin Tucker
Ungar, 1988
Buku Referensi
edited by Jack A. Goldstone, Ted Robert Gurr, Farrokh Moshiri
Westview Press, 1991
Buku Teks
Varga, Eugen, 1879-1964, author
Foreign Languages Publishing House, 1961
Buku Teks
Kohn, Hans, author
D. Van Nostrand, 1965
Buku Teks