Sentence-Based Natural Language Plagiarism Detection
This paper details a novel algorithm for comparison of suspect documents at a sentence level and has been implemented as a component of plagiarism detection software for detecting similarities in both natural language documents and comments within program source code.
http://doi.acm.org/10.1145/1086339.1086341
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It could be useful to implement a plagiarism detection system for conference papers. I remember we used to manually find copied papers on the internet during the Vidyakash 2002/KBCS 2002 conferences.