Harley, John P., author
McGraw-Hill Book, 2000
Buku Teks
Woods, A.E., author
The Avi Publishing, 1977
Buku Teks
Tillery, Bill W., author
McGraw-Hill, 2008
Buku Teks
Mandl, Matthew, author
Prentice-Hall, 1967
Buku Teks
Anderson, J. M., editor
CAB International, 1993
Buku Referensi