6Brinley Franklin.Managing the Electronic Collection with Cost per Use Data.http:/www.ifla.org(2005-01-03)
7Charles T.Townley and Leigh Murray,Use-Based Criteria for Selecting and Retaining Electronic Information:A Case Study,"Information Technology and Libraries,1999(1)
8http://www.arl.org(2004-03-01)
9ISO11620 Information and documentation-Library performance indicators:1998/Amd.1:2003(E),Switzerland
10M.J.Devanter and R.Snyman.Measuring for Sustainability:A Multi-dimensional Measurement Framework for Library and Information Services.Libri.2004(54)