edited by Jose I. Furtado
Harwood Academic , 1990.
Buku Teks
Marcus, Edward, author
Bookman Associates, 1960
Buku Teks
Due, John F., author
MIT Press, 1963
Buku Teks
Havinden, Michael, author
Routledge, 1993
Buku Teks
Davidson, B.R., author
Melbourne University Press, 1972
Buku Teks