Stein, Theodore J., author
Columbia University Press, 2001
Buku Teks
Hickman, Bert G., author
The Brooking Institution , 1965
Buku Teks
edited and introduced by Andrew Shonfield and Stella Shaw
Heinemann Educational Books, 1972
Buku Teks
edited by James Midgley, David Piachaud
St. Martin's Press, 1984
Buku Teks
Cooper, Robert L., author
Cambridge University Press, 1989
Buku Teks