G. Lindgaard, und J. Chattratichart. CHI '07: Proceedings of the SIGCHI conference on Human factors in computing systems, Seite 1415--1424. New York, ACM, (2007)
M. Hassenzahl, A. Platz, M. Burmester, und K. Lehner. Proceedings of the CHI 04 Conference on Human Factors in Computing Systems. Extended abstracts, Seite 1283-1286. New York, ACM, (2000)