Thomas Ågotnes Wiebe van der Hoek Moshe Tennenholtz Michael Wooldridge Power in normative systems. 145-152 2009 AAMAS (1) http://doi.acm.org/10.1145/1558013.1558033 conf/atal/2009-1 db/conf/atal/aamas2009-1.html#AgotnesHTW09