Greenbaum, Sidney
Longman , 1990
Buku Teks
Huddleston, Rodney, author
Melbourne University Press, 1984
Buku Teks
Anderson, W.M. (Wendy M.), author
Wiley Publishing , 2013
Buku Teks
Woods, Geraldine, author
John Wiley & Sons, 2016
Buku Teks
House, C. Homer, author
Prentice-Hall, 1950
Buku Teks