Kovacs, Diane K.
The virtual reference handbook : interview and information delivery techniques for the chat and e-mail environments
Facet Publishing, 2007
 Buku Referensi
Kern, M. Kathleen
Virtual reference best practices: tailoring services to your library
American Management Association, 2009
 eBooks
Hani Kusumaningsih
Evaluasi layanan referensi e-mail Perpustakaan United Nations Information Centre Jakarta = Evaluation of e-mail reference at United Nations Information Centre Library Jakarta
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2016
 UI - Skripsi Membership
The virtual reference desk: creating a reference future
David R. Lankes ... [and others]
Facet Publishing, 2006
 Buku Teks SO
Pace, Andrew K.
The ultimate digital library: where the new information players meet
[American Library association, ], 2003
 eBooks