Dawei Hu Shenhua Gu Shitong Wang Liu Wenyin Enhong Chen Question recommendation for user-interactive question answering systems. 39-44 2008 ICUIMC http://doi.acm.org/10.1145/1352793.1352803 conf/icuimc/2008 db/conf/icuimc/icuimc2008.html#HuGWWC08