Nussbaum, Arthur, author
Macmillan, 1958
Buku Teks
Plucknett, Theodore F. T.
Little, Brown and Company, 1956
Buku Teks
Fawcett, J.E.S., author
Penguin Books, 1971
Buku Teks
Younger, R. M.
Victoria Hutchinson Group 1982
Buku Teks
Goldschmidt, Arthur, author
Westview Press, 1983
Buku Teks