Sherry, John C.
Collier Books, 1963
Buku Teks
Mott, George Fox
Barnes & Noble, Inc., 1957
Buku Teks
Rickard, J.A.
Barnes & Noble, 1952
Buku Teks
compiled and edited by William L. Langer
Houghton Mifflin, 1968
Buku Referensi
McGarry, Daniel D.
Littlefield, Adams, 1968
Buku Teks