Shen, C., T. Li, and C. Ding. “Integrating Clustering and Multi-Document Summarization by Bi-Mixture Probabilistic Latent Semantic Analysis (PLSA) With Sentence Bases”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 25, no. 1, Aug. 2011, pp. 914-20, doi:10.1609/aaai.v25i1.7977.