Artikel Jurnal
edited by Milton Abramowitz, Irene A. Stegun
U.S. Government Printing Office, 1967
Buku Referensi
Epstein, Benjamin, author
CRC Press (Taylor & Francis Group), 2008
Buku Teks
Bartholomew, David J., author
John Wiley & Sons, 1981
Buku Teks
Wheeler, Roger F., author
Ellis Horwood, 1981
Buku Teks