Srivastava, A.C., author
Vani Educational Books, [Date of publication not identified]
Buku Teks
Turner, J.D., author
Macmillan, 1988
Buku Teks
Eckman, Donald P., author
Wiley, 1950
Buku Teks
Darrell R. Jobman, editor
Irwin, 1995
Buku Referensi
McGraw-Hill, 1961
Buku Referensi