3Association of Research Library,Measures for Electronic Resources, E-Metrics [ EB/OL ]. [ 2008-06-09]. http://eric. ed.gov/ERICDocs/data/ericdocs2sql/content-storage-01/0000019b/80/1a/b 1/80.pdf.
4ANNEXA : Measuring the Use of Electronic Library Services [ EB/OL ]. [ 2008 -06 -09 ].http://www.iso.org/iso/catalogue_detail?csnumber=-28236.
5National Information Standards Organization, NISO ,Information Service and Use: Metrics & statistics for libraries and information providers-data dictionary [EB/OL]. [2008- 04-15 ].http://www.niso.org/dictionary/.
8International Coalition of Library Consortia (ICOLC), Guidelines for Statistical Measures of Usage of Web-based Information Resources. [ EB/OL ]. [ 2008-04-15 ].http://www.library. yale.edu/consortia/webstats063htm.