Ullrich Köthe Peer Stelldinger Shape Preserving Digitization of Ideal and Blurred Binary Images. 82-91 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2886&spage=82 2003 conf/dgci/2003 DGCI db/conf/dgci/dgci2003.html#KotheS03