Dumbauld, Edward, author
University of Oklahoma Press, 1946
Buku Teks
Antieau, Chester James, author
Dennis & Co., 1960
Buku Teks
Bemis, Samuel Flagg, 1891-1973, author
Holt, Rinehart and Winston, 1965
Buku Teks
Myers, Margaret G., author
Columbia University Press , 1970
Buku Teks
Fairbank, John K. (John King), author
The Viking Press, 1968
Buku Teks