Sharkansky, Ira
McGraw-Hill, 1975
Buku Teks
Gerston, Larry N.
Scott Foresman and Company, 1983
Buku Teks
Hird, John A.
Wadsworth , 2004
Buku Teks
Peters, B. Guy
Sage , 2013
Buku Teks
edited by Allan P. Sindler ; contributors: Edward C. Banfield ... [et. al.].
Little, Brown, 1973
Buku Teks