Hansen, Harry, author
A Mentor Book, 1961
Buku Teks
Frazier, Charles
Vintage Books , 1997
Buku Teks
Ketchum, Richard M., author
American Heritage Publishing, 1960
Buku Teks
Bryan, J.
McGraw-Hill Book Company, Inc., 1960
Buku Teks
Avon Book Division, 1961
Buku Teks