Benet, William Rose
Thomas Y. Crowell, 1965
Buku Referensi
edited by Joseph T. Shipley
Littlefield, Adams, 1960
Buku Referensi
Watt, Homer A.
Barnes & Noble, 1957
Buku Referensi
Hart, James
Oxford University Press, 1965
Buku Referensi
Harkins, William E.
Littlefield, Adams, 1959
Buku Referensi