5[1]Ann Marie Parasons.Digital reference:How Libraries Can Compet with Aska Service.DLF Newsletter January 2001 . http://www.diglib.org/
6Chowdhury, G.G. Digital libraries and reference services: present and future. Journal of Documentation, 2002, 58 (3).
7http://www. vrd. org/about. shtml
8Carol Tenopir. Virtual Reference Services in a Real World. Library Journal 2001(12):38
9Soo Young Rieh. Changing Reference Service Environmerit: A Review of Perspectives from Managers,Librarians, and Users. The Journal of American Librarianship,1999(3) : 178-186
10Chris Ferguson, shaking the conceptual foundation, too:integrating research and technology support for the nex tgeneration of information service. College and research libraries,2000(4) :300-311
