Gramley, Stephan
Routledge, 2004
Buku Teks
Frank, Marcella
Prentice-Hall, 1972
Buku Teks
New, W.H.
Copp Clark Pitman, 1986
Buku Teks
Crowell, Thomas Lee
McGraw-Hill, 1987
Buku Referensi
Fowler, H. W. (Henry Watson), 1858-1933
Oxford University Press, 1983
Buku Referensi