Koutrika, G., Effendi, F. A., Gyöngyi, Z., Heymann, P. & Garcia-Molina, H. (2007). Combating spam in tagging systems. AIRWeb '07: Proceedings of the 3rd international workshop on Adversarial information retrieval on the web (p./pp. 57--64), New York, NY, USA: ACM Press. ISBN: 978-1-59593-732-2