Stryker, Perrin, author
Harper & Row, 1960
Buku Teks
Swamy, Narayan, author
Vijitha Yapa Publications, 2006
Buku Teks
Pope, Harrison G., author
Simon & Schuster , 2002
Buku Teks
Seagle, William
Hafner Publising Copmpany, 1971
Buku Teks
Book World, 1933
Buku Teks