4N. Beagrie, D. Greenstein. A strategic policy framework for creating and preserving digital collections, http://vads. ahds. ac. uk/guides/creating_guide/sect72, html(2005-07-20).
5The Data Archive, University of Essex. An investigation into the digital preservation needs of universities and research funders:the future of unpublished research materials, http://www. ukoln. ac. uk/services/papers/bl/blril09/datrep, html(2005-07-30).
6D. Hazen,et. al. Selecting research collections for digitization, http://eprints, ucl. ac. uk/archive/00000492/01/paul_ayris3, pdf(2005-07-30).
7Paul Ayris. Guidance for Selecting Materials for Digitisation. http://www. rig. org/preserv/joint/ayris. html(2005-07-30).
8Katherine M. Wisser . Guidelines for Digitization. http ://www. ncecho. org/Guide/toc. htm(2005-07-30).
9Library of Congress. Selection Criteria for Preservation Digital Reformatting. http://www.loc.gov/preserv/prd/presdig/presselection, html(2005-07-30).
10Columbia University Libraries Selection Criteria For Digital Imaging. http://www. columbia, edu/cu/libraries/digital/criteria, html(2005-07-30).
