Mendenhall, William, author
Cal Duxbury Press , 1971
Buku Teks
by Collin J. Watson [and others]
Allyn and Bacon, 1993
Buku Teks
Kahn, Alfred E.
John Wiley & Sons Inc, 1995
Buku Teks
Samuelson, Paul Anthony, 1915-2009, author
McGraw-Hill, 2010
Buku Teks
Lipsey, Richard G., author
Harper Collin, 1996
Buku Teks