Bentley, John Edward
Littlefield, Adams, 1958
Buku Teks
Rader, Melvin
Holt, Rinehart and Winston, 1966
Buku Teks
Mulvaney, Robert J.
Essex Pearson, 2014
Buku Teks
editor, James A. Gould
Charles E. Merrill , 1971
Buku Teks
edited by John K. Ryan
The Catholic University of America Press, 1963
Buku Teks