Alford, B.W.E.
Macmillan, 1988
Buku Teks SO
Hubbard, G.E.
International Secretariat Institute of Pasific Relations, 1943
Buku Teks
Egerton, Hugh Edward
Methuen, 1905
Buku Teks SO
Cullingworth, J.B.
Allen & Unwin, 1979
Buku Teks SO
Rifki Firdaus
2010
UI - Skripsi Open