Charlesworth, M. P., author
Oxford University Press, 1951
Buku Teks
Gibbon, Edward
Random House , 1993
Buku Referensi
Hayes, Carlton J. H., author
Macmillan, 1932
Buku Teks
Souliw, Charles Georges, author
J. Cape & H. Smith, 1931
Buku Teks
Boren, Henry C., author
D.C. Heath and Company, 1977
Buku Referensi