Gordon, Lois
Yale University Press, 1999
Buku Teks
Morse, Arthur D.
Random House, 1968
Buku Teks
ECAM Publications, 1989
Buku Teks
Brogan, D.W. (Denis William), author
Oxford University Press, 1950
Buku Teks
Mauk, David, author
Routledge, 1997
Buku Teks