Cattuto, Ciro, Baldassarri, Andrea, Servedio, Vito D. P., Loreto, Vittorio: Vocabulary growth in collaborative tagging systems. In: , 2007

Sen, Shilad, Lam, Shyong K., Rashid, Al Mamunur, Cosley, Dan, Frankowski, Dan, Osterhouse, Jeremy, Harper, F. Maxwell, Riedl, John: tagging, communities, vocabulary, evolution. In: CSCW '06: Proceedings of the 2006 20th anniversary conference on Computer supported cooperative work. New York, NY, USA : ACM, 2006. - ISBN 1-59593-249-6, S. 181--190

Furnas, G. W., Landauer, T. K., Gomez, L. M., Dumais, S. T., The vocabulary problem in human-system communication, in: Commun. ACM 30 (1987), S. 964--971.