Edited by Robert F. Durant, Jennifer R.S. Durant
CRC Press, 2013
Buku Teks
Herring, E. Pendleton, author
McGraw-Hill, 1936
Buku Teks
Simon, Herbert A., author
Alfred A. Knopf, 1973
Buku Teks
Bartholomew, Paul C., author
Littlefield, Adams, 1959
Buku Teks
edited by Robert T. Golembiewski, Frank Gibson, Geoffrey Y. Cornog
Rand McNally College, 1972
Buku Teks