Krzysztof R. Apt Vincent Conitzer Mingyu Guo Evangelos Markakis Welfare Undominated Groves Mechanisms. 426-437 2008 WINE http://dx.doi.org/10.1007/978-3-540-92185-1_48 conf/wine/2008 db/conf/wine/wine2008.html#AptCGM08