Adams, Michael Vannoy
Routledge, 1996
Buku Teks
Atkinson, Paul, author
Routledge, 1994
Buku Teks
Burden, Ernest E., 1934-, author
McGraw-Hill, 2000
Buku Teks
Koelb, Clayton, author
Cornell University Press , 1988
Buku Teks
Schaller, Thomas Wells, author
Van Nostrand Reinhold, 1997
Buku Teks