Comeau, Raymond F.
Holt, Rinehart, and Winston, 1986
Buku Teks
Bickerton, Ian J.
Prentice-Hall, 1991
Buku Teks
Capehart, Barney L.
The Fairmont Press, Inc., 2008
Buku Teks
Butters, J. Keith
Harvard University Press , 1951
Buku Teks
Johnson, Lewis K., author
Allyn and Bacon, 1957
Buku Teks