compiled by S.K Baker
Oxford Publishing, 1984
Buku Referensi
Watson, W.C.R., author
At The University Press, 2013
Buku Teks
The Automobile Association, 1990
Buku Referensi
Pearson, J. D, author
Royal Asiatic Society, 1954
Buku Teks
London : Ditching Press Limited
Majalah, Jurnal, Buletin