Feng Yu 0021 Hong-wei Xuan Dequan Zheng Key-Phrase Extraction Based on a Combination of CRF Model with Document Structure. 406-410 2012 CIS https://doi.org/10.1109/CIS.2012.97 https://doi.ieeecomputersociety.org/10.1109/CIS.2012.97 conf/cis/2012 db/conf/cis/cis2012.html#YuXZ12