Thampan, Palakasseril Kumaran
Oxford & IBH Publishing Co., 1981
Buku Referensi
edited by Linn C. Stuckenbruck
Addison-Wesley, 1981
Buku Referensi
Calvo, Clara, author
Routledge, 1998
Buku Teks
Peterson, Veronica, author
Elsevier Mosby, 2013
Buku Teks
Gipson, James H.
McGraw-Hill Book, 1984
Buku Teks