Mass., A. J. St. Onge, 1970
Buku Teks
Dumbauld, Edward
University of Oklahoma Press, 1950
Buku Teks
D.C. Heath and Company, 1976
Buku Teks
McGee, Dorothy Horton, author
Dodd, Mead, 1953
Buku Teks
edited by Carl J. Friedrich, Robert G. McCloskey
The Liberal Arts Press, 1954
Buku Teks