Bedford, Henry F., author
Harcourt Brace Jovanovich, 1972
Buku Teks
compiled by Jonathan French Scott and Alexander Baltzly
F.S. Crofts & Co., 1930
Buku Teks
Solberg, Carle
Stanford University Press, 1979
Buku Teks
Fredrickson, George M., author
Univ. of California Press, 2000
Buku Teks
Christie, Clive J., author
Tauris Academic, 1996
Buku Teks