H. v. Kortzfleisch, I. Mergel, S. Manouchehri, and M. Schaarschmidt. Web 2.0 Neue Perspektiven im E-Business, Web 2.0 Neue Perspektiven für Marketing und Medien, Springer Verlag, Berlin, Web 2.0 Neue Perspektiven für Marketing und Medien.(2007)
X. Amatriain, N. Lathia, J. Pujol, H. Kwak, and N. Oliver. SIGIR '09: Proceedings of the 32nd international ACM SIGIR conference on Research and development in information retrieval, page 532--539. New York, NY, USA, ACM, (2009)
W. Jones, A. Phuwanartnurak, R. Gill, and H. Bruce. CHI '05: CHI '05 extended abstracts on Human factors in computing systems, page 1505--1508. New York, NY, USA, ACM, (2005)