Passage retrieval vs document retrieval for factoid question answering Charles L. A. Clarke and Egidio L. Terra Return to Posters BIBTEX @inproceedings       {DBLP:conf/sigir/ClarkeT03,   author    = {Charles L. A. Clarke and                 Egidio L. Terra},    booktitle = {SIGIR},    title     = {Passage retrieval vs. document retrieval for factoid question answering.},    pages     = {427-428},    year      = {2003},    url       = {db/conf/sigir/sigir2003.html#ClarkeT03},    ee        = {http://doi.acm.org/10.1145/860534},    crossref  = {conf/sigir/2003},    bibsource = {DBLP, http://dblp.uni-trier.de}  } ©2004 Association for Computing Machinery