L. Denoue, J. Adcock, S. Carter, P. Chui, and F. Chen. Proceedings of the 10th ACM symposium on Document engineering - DocEng '10, page 235. Manchester, United Kingdom, ACM Press, (2010)
P. Fröhlich, M. Baldauf, S. Suette, D. Schabus, and M. Fuchs. Proceedings of the 2012 ACM annual conference on Human Factors in Computing Systems (CHI), Extended Abstracts, page 1787-1792. Austin, TX, USA, (May 2012)