Karrass, Chester L.
Thomas Y. Crowell, 1970
Buku Teks SO
Durrant, Fiona
Facet Publishing, 2006
Buku Teks
Hoovers Institution Press, 1978
Buku Teks SO
University of Queensland Press : The Australian Studies Centre
Majalah, Jurnal, Buletin
World Peace Foundation, 1951
Buku Teks