Artikel Jurnal
Davis, Angela Y. (Angela Yvonne), 1944 -. author
Haymarket Books, 2016
Buku Teks SO
Polsby, Nelson W.
Charles Scribner's Sons, 1980
Buku Teks SO
Kitzinger, Uwe W.
Clarendon Press, 1960
Buku Teks SO
Morgenthau, Hans J.
Alfred A. Knopf, 1950
Buku Teks SO