Prytherch, Ray, author
Gower, 1987
Buku Referensi
Renato M. Natal Jorge, Joao Manuel R.S. Tavares, Marcos Pinotti Barbosa, A.P. Slade, editor
[, Springer], 2012
eBooks
edited by Diane H. Sonnenwald
Universityy of Texas Press, 2016
Buku Teks
Blazek, Ron, author
Libraries Unlimited, 2000
Buku Referensi
Stewart, David W., author
Sage, 1984
Buku Teks