7Levine-Clark M. Developing a Multiformat Demand-Driven Acquisition Model[J].Collection Management, 2010(3-4) : 201-207.
8Fischer K S, wright M, Clatanoff K,et al. Give 'Em What They Want: A One-Year Study of Unmediated P.atron-Driven Acquisition of E- Books[J].College & Research Libraries, 2012(9):469-492.
9The Rise of E-Reading[EB/OL].[2013-O4-15].http://libraries pewinternet.org/2012/04/0g/the-rise-of-e-reading/.