Chandra, Prakash
Vikas Publishing House, 1982
Buku Teks
Rourke, John T.
McGraw-Hill, 2010
Buku Teks
Lerche, Charles O., Jr.
Oxford University Press, 1956
Buku Teks
Padelford, Norman J.
Macmillan, 1962
Buku Teks
Rourke, John T.
McGraw-Hill, 2001
Buku Teks