1. Adomavicius G, Tuzhilin A (2005) Toward the next generation of recommender systems: a survey of the state-of-the-art and possible extensions. IEEE Trans Knowl Data Eng 17(6):734–749
2. Albanese M, Chianese A, d’Acierno A, Moscato V, Picariello A (2009) A recommendation system for browsing digital libraries. In: SAC ’09: proceedings of the 24th symposium on applied computing. ACM, Honolulu pp 1771–1778
3. Anand SS, Kearney P, Shapcott M (2007) Generating semantically enriched user profiles for web personalization. ACM Trans Internet Technol 7(4):22
4. Basilico J, Hofmann T (2004) Unifying collaborative and content-based filtering. In: ICML ’04: proceedings of the 21st international conference on machine learning, ACM, Banff
5. Ciaccia P, Patella M, Zezula P (1997) M-tree: an efficient access method for similarity search in metric spaces. In: Jarke M, et al. (eds) VLDB 97: proceedings of 23rd conference on very large database. Morgan Kaufmann, Athens, pp 426–435