J. Chang, J. Boyd-Graber, und D. Blei. KDD '09: Proceedings of the 15th ACM SIGKDD international conference on Knowledge discovery and data mining, Seite 169--178. New York, NY, USA, ACM, (2009)
Y. Liu, A. Sprague, und E. Lefkowitz. ACM-SE 42: Proceedings of the 42nd annual Southeast regional conference, Seite 402--103. New York, NY, USA, ACM, (2004)