Gray, Colin S., author
Simon & Schuster, 1990
Buku Teks
Lawrence, Mark Atwood, author
Oxford University Press, 2010
Buku Teks
edited Steven L. Spiegel
St. Martin's Press, 1981
Buku Teks
Woodby, Sylvia
Westview Press, 1988
Buku Teks
The John Hopkins University Press, 1979
Buku Teks