Sharkansky, Ira
McGraw-Hill, 1975
Buku Teks
Dolbeare, Kenneth M.
D.C. Heath, 1985
Buku Teks
Rourke, Francis E.
Little, Brown, 1979
Buku Teks
by James E. Anderson; David Brady; Charles Bullock III; Joseph stewart, JR
Brooks/Cole; cengage learning, 1984
Buku Teks
Manley, John F.
Macmillan, 1976
Buku Teks