Cobban, Alfred, author
Collins Clear-Type Press, 1969
Buku Teks
Bunbongkarn, Suchit
Institute of southeast Asian studies, 1996
Buku Teks
Adrian, Charles R., author
Mc Graw-Hill, 1976
Buku Teks
Artikel Jurnal
Hansen, Alvin H. (Alvin Harvey), 1887-1975, author
George Allen and Unwin, 1944
Buku Teks