Abell, George O., author
Holt Rinehart and Winston, 1974
Buku Teks
McFadden, Carol Hardy, author
W.W. Norton, 1995
Buku Teks
Swales, John M., author
Cambridge University Press, 2004
Buku Teks
Kottak, Conrad Phillip, 1942-, author
Random House, 1974
Buku Teks
Peters, William C.
John Wiley & Sons, 1987
Buku Teks