A. Bellogin, P. Castells, и I. Cantador. Proceedings of the fifth ACM conference on Recommender systems - RecSys 2011, стр. 333 -- 336. ACM Press, (2011)
S. Doerfel, D. Zoller, P. Singer, T. Niebler, A. Hotho, и M. Strohmaier. Proceedings of the 16th LWA Workshops: KDML, IR and FGWM, Aachen, Germany, September 8-10, 2014., том 1226 из CEUR Workshop Proceedings, стр. 18--19. CEUR-WS.org, (2014)