United Nations Educational, Scientific and Cultural Organization, 1977
Buku Teks
The Viking Press, 1943
Buku Teks
Artikel Jurnal
Churchill, Winston, Sir, 1874-1965, author
Simon and Schuster, 1946
Buku Teks
Cole, Fay-Cooper, author
D. Van Nostrand, 1945
Buku Teks