E. Bakshy, J. Hofman, W. Mason, und D. Watts. Proceedings of the fourth ACM international conference on Web search and data mining, Seite 65--74. New York, NY, USA, ACM, (2011)
M. Hill, H. de Waardt, und H. Dorren. Lasers and Electro-Optics, 2001. CLEO '01. Technical Digest. Summaries
of papers presented at the Conference on, Seite 188--. (2001)