pdf dblp IIIT Hyderabad at Million Query Track TREC 2009 Prashant Ullegaddi | Sudip Datta | Vinay Pande | Kushal S. Dave | Vasudeva Varma Proceedings of The Eighteenth Text REtrieval Conference, TREC 2009, Gaithersburg, Maryland, USA, November 17-20, 2009