Jonathan Chang and Jordan Boyd-Graber and David M. BleiKDD '09: Proceedings of the 15th ACM SIGKDD international conference on Knowledge discovery and data mining, page 169--178. New York, NY, USA, ACM, (2009)
Ying Liu and Alan P. Sprague and Elliot LefkowitzACM-SE 42: Proceedings of the 42nd annual Southeast regional conference, page 402--103. New York, NY, USA, ACM, (2004)
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