Moore, Harriet
Princeton University Press, 1945
Buku Teks
Bisson, T.A.
Macmillan, 1945
Buku Teks SO
Hubbard, G.E.
International Secretariat Institute of Pasific Relations, 1943
Buku Teks
Bisson, T.A.
International Secretariat Institute of Pasific Realtions , 1945
Buku Teks
Griswold, Alfred Whitney, 1906-1963
Harcourt, Brace , 1938
Buku Teks SO