Macridis, Roy C.
Little, Brown, 1983
Buku Teks SO
Hague, Rod.
Palgrave Macmillan , 2013
Buku Teks SO
Curtis, Michael
Harper & Row, 1978
Buku Teks SO
Kesselman, Mark
Wadsworth and Cengage Learning, 2013
Buku Teks SO
by Carlton Clymer Rodee ... [and others]
McGraw-Hill Kogakusha, 1976
Buku Teks SO