Demmer, Ulrich, author
Oxford University Press, 2016
eBooks
Kothari, Rajni, author
Little, Brown, 1970
Buku Teks
edited by Manjulika Dubey and Bikram Grewal
Hofer Press, 1992
Buku Referensi
Sharma, I.C.
Johsen Publishing Company, 1965
Buku Teks
Robinson, Marguerite S., author
Oxford University Press, 1988
Buku Teks