Incollection (jaeschke2012challenges)
Jäschke, R.; Hotho, A.; Mitzlaff, F. & Stumme, G.
Kacprzyk, J. & Jain, L. C. (ed.)
Challenges in Tag Recommendations for Collaborative Tagging Systems
Springer, 2012, 32, 65-87

Article (Herlocker:2004:ECF:963770.963772)
Herlocker, J. L.; Konstan, J. A.; Terveen, L. G. & Riedl, J. T.
Evaluating collaborative filtering recommender systems
ACM Trans. Inf. Syst., ACM, 2004, 22, 5-53