Rudelius, William, author
Harcourt Brace Jovanovich , 1973
Buku Teks
Moore, Charles Willard, 1925-1993, author
MIT Press, 1993
Buku Teks
Berkowitz, Eric N.
St. Louis, Times Mirror/Mosby College Pub
Buku Teks
Baumol, William J.
New York, N.Y. : Macmillan, 1959,
Buku Teks
Martin's, 2005
Buku Teks