J. O'Donovan, and B. Smyth. IUI '05: Proceedings of the 10th international conference on Intelligent user interfaces, page 167--174. New York, NY, USA, ACM Press, (2005)
K. McNally, M. O'Mahony, B. Smyth, M. Coyle, and P. Briggs. Proceedings of the 16th international conference on Intelligent user interfaces, page 387--390. New York, NY, USA, ACM, (2011)