Evaluation of reference services / edited by Bill Katz and Ruth A. Fraley
Haworth Press, 1984
 Buku Referensi
Lankes, R. David
Implementing digital reference services : setting standards and making it real
Facet Publishing, 2003
 Buku Teks
Kern, M. Kathleen
Virtual reference best practices: tailoring services to your library
[American Management Association, ], 2009
 eBooks
McMenemy, David
Delivering digital services : a handbook for public libraries and learning centres
Facet, 2006
 Buku Referensi
Cassell, Kay Ann
Reference and information services : an introduction
Neal-Schuman, an imprint of the American Library Association, 2013
 Buku Teks