Hughes, Robert, author
Alfred A. Knopf, 1997
Buku Teks
Richards, Jeffrey
Routledge and Kegan Paul, 1973
Buku Teks
Whitman, Howard
Prentice-Hall, 1961
Buku Teks
Stewart, Hugh B.
Dow Jones-Irwin, 1989
Buku Teks
edited by Paul Harrison
Oxford University Press, 1996
Buku Teks