Kenyon, John Samuel
Merriam-Webster ; G. & C. Merriam Co., 1953
Buku Referensi
MacCarthy, Peter A.
Heffer, 1950
Buku Teks
edited by Frank O. Colby
Thomas Y. Crowell, 1950
Buku Referensi
Jones, Daniel
Dent, 1940
Buku Referensi
Nilsen, Don L. F.
Regents Publishing, 1973
Buku Teks