Brinton, Crane, 1898-1968, author
Prentice-Hall, 1955
Buku Teks
McKay, John P., author
Houghton Miffiln, 1984
Buku Teks
Muller, Herbert J.
A Mentor Books, 1957
Buku Teks
De Burgh, W.G. (William George), 1866-1943
Penguin Books, 1953
Buku Teks
Fischer, Eric, author
Harvard University Press, 1943
Buku Teks