Enhancing Extraction of Drug-Drug Interaction from Literature Using Neutral Candidates, Negation, and Clause Dependency Bokharaeian, Behrouz ; Diaz, Alberto ; Chitsaz, Hamidreza Abstract Publication: PLoS ONE Pub Date: October 2016 DOI: 10.1371/journal.pone.0163480 Bibcode: 2016PLoSO..1163480B