7De Groote, S. L. Quantifying cooperation: Collaborative digital reference service in the large academic library [ J ]. College & Research Libraries,2005,66 (5) 436 - 454.
8Marie L. Radford, M. Kathleen Kern. A multiple - case study investigation of the discontinuation of nine chat reference services [ J ]. Library & Information Science Research 2006,28:521 -547.
9Jane T. Bradford, Barbara Costello, and Robert Lenholt. Reference Service in the Digital Age: An Analysis of Sources Used to Answer Reference Questions[ J]. The Journal of Academic Librarianship ,2005,31 ( 3 ) :263 - 272.
10Smiti Gandhi. Knowledge Management and Reference Services [ J ]. The Journal of Academic Librarianship,2004,30 ( 5 ) :368 - 381.