Rivers, Wilga M., author
Cambridge University Press, 1985
Buku Teks
edited by Duddley Bailey
W.W. Norton, 1965
Buku Teks
St. Martin's press, 1981
Buku Teks
edited by Norman Page
Macmillan, 1984
Buku Teks
Lyons, John, author
Cambridge University Press, 1991
Buku Teks