Forsythe, David P., 1941-, author
Cambridge University Press, 2000
Buku Teks
Shelton, Dinah L., author
Edward Elgar, cop, 2014
Buku Teks
Gibson, John S., author
Praeger, 1991
Buku Teks
Selby, David, author
Cambridge University Press, 1988
Buku Teks
edited by Dianne Otto
Edward Elgar, 2013
Buku Referensi