Alberto H. F. Laender Marcos André Gonçalves Ricardo G. Cota Anderson A. Ferreira Rodrygo L. T. Santos Allan J. C. Silva Keeping a digital library clean: new solutions to old problems. 257-262 2008 ACM Symposium on Document Engineering http://doi.acm.org/10.1145/1410140.1410195 conf/doceng/2008 db/conf/doceng/doceng2008.html#LaenderGCFSS08