@inproceedings { han13,
	booktitle = {K. Hindriks, M. de Weerdt (eds.), Procs. The 25th Benelux Conference on Artificial Intelligence (BNAIC 2013), November 7-8, Delft, The Netherlands, 2013},
	keywords = {Game Theory;Multi-Agent Societies;},
	title = {Why is it so hard to say sorry?},
	year = {2013},
	author = {T. A. Han and L. M. Pereira and Francisco C. Santos and Tom Lenaerts}
}