Henry, Nicholas
Prentice-Hall, 1975
Buku Teks
National Library of Australia, 1993
Majalah, Jurnal, Buletin
Public Affairs Information Service, 1946
Buku Teks
Brannan, Tom, author
PPM, 2005
Buku Teks
Intner, Sheila S., author
Libraries Unlimited, 2001
Buku Teks