S. Zerr, S. Siersdorfer, J. Hare, and E. Demidova. Proceedings of the 35th international ACM SIGIR conference on Research and development in information retrieval SIGIR 2012, page 35-44. ACM, (2012)
G. Styliaras, and S. Christodoulou. HT '09: Proceedings of the Twentieth ACM Conference on Hypertext and Hypermedia, New York, NY, USA, ACM, (July 2009)