1. Abigail, Re: Random number in perl, Posting in the newsgroup comp.lang.perl.misc, Message-ID slrn64sudh.qp.abigail@betelgeuse.wayne.fnx.com, 1997.
2. Algorithms for finding patterns in strings;Aho,1990
3. Finding patterns common to a set of strings;Angluin;J. Comput. Syst. Sci.,1980
4. Expressive languages for path queries over graph-structured data;Barceló,2010
5. Learning deterministic regular expressions for the inference of schemas from XML data;Bex;ACM Trans. Web,2010