6Mitra M,Chaudhuri B B.Information Retrieval from Documents:A survey.Information Retrieval[J].2000,2(2):141-163.
7Tan C L,Huang W,Yu Z,et al.Imaged Document Text Retrieval without OCR.IEEE Trans.Pattern Analysis and Machine Intelligence[J].2002,24 (6):838-844.
8Doermann D,Sauvola J,Kauniskangas H,et al.The development of a general framework for intelligent document image retrieval[A].In:The 3rd intl workshop on Document Analysis Systems[C].Malvern,Pennsylvania,USA,1996.605-632.
9Doermann D,Li H,Kia O.The detection of duplicate in document image database.Image and Vision Computing[J].1998,16(12):907-920.
10Niyogi D,Srihari S.The Use of Document Structure Analysis to Retrieve Information from Documents in Digital Libraries[A].In:Proc SPIE,Document Recoginition Ⅳ[C].1997.3027:207-218.