Jennifer Chu-Carroll Krzysztof Czuba John M. Prager Abraham Ittycheriah Sasha Blair-Goldensohn IBM's PIQUANT II in TREC 2004. 2004 TREC http://trec.nist.gov/pubs/trec13/papers/ibm-prager.qa.pdf conf/trec/2004 db/conf/trec/trec2004.html#Chu-CarrollCPIB04