A facility for navigating an electronic document is described. The facility receives user input selecting a portion of the content of a rendered document that constitutes a sentence fragment. In response to receiving the user input, the facility identifies an electronic document contained in a corpus...http://www.google.com.tw/patents/US7702624?utm_source=gb-gplus-share專利 US7702624 - Processing techniques for visual capture data from a rendered document
