A. Scaria, R. Philip, R. West, и J. Leskovec. Proceedings of the 7th ACM international conference on Web search and data mining, стр. 213--222. ACM, (2014)
J. Li, S. Huffman, и A. Tokuda. 32nd Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, стр. 43-50. (2009)