Leif Azzopardi, Mark Baillie, Ian Ruthven. Persuasive, Authorative and Topical Answers for Complex Question Answering. In Ellen M. Voorhees, Lori P. Buckland, editors, Proceedings of The Sixteenth Text REtrieval Conference, TREC 2007, Gaithersburg, Maryland, USA, November 5-9, 2007. Volume Special Publication 500-274 of National Institute of Standards and Technology (NIST), 2007. [doi]