University of California Press, 1963
Buku Teks
edited by Sharon B. Sticher, Jane L. Partpart
Westview Press, 1988
Buku Teks
edited by John C. Caldwell and Chukuka Okonjo
Longmans, Green, 1968
Buku Teks SO
Due, John F., author
MIT Press, 1963
Buku Teks
University of California Press, 1966
Buku Teks