Beard, Charles A., author
New Home Library, 1944
Buku Teks
Beard, Charles A., author
Dobleday, 1960
Buku Teks
Myers, Gustavus, author
Random House, 1943
Buku Teks
Myers, Margaret G., author
Columbia University Press , 1970
Buku Teks
Kemmerer, Donald L., author
Littlefield, Adams, 1956
Buku Teks