Vladimirov, P.P.
Allied Publishers, 1974
Buku Teks
Elegant, Robert S.
Twayne Publishers, 1951
Buku Teks
Rosinger, Lawrence K., author
Princeton, 1944
Buku Teks
edited by Ian Wilson
Angus and Robertson, 1973
Buku Teks
Barnett, Arthur Doak, author
Frederick A. Praeger, 1962
Buku Teks