Evaluating and combining and biomedical named entity recognition systems Andreas Vlachos author 2007-06 text Biological, translational, and clinical language processing K Bretonnel Cohen editor Dina Demner-Fushman editor Carol Friedman editor Lynette Hirschman editor John Pestian editor Association for Computational Linguistics Prague, Czech Republic conference publication vlachos-2007-evaluating https://aclanthology.org/W07-1031/ 2007-06 199 200