Takao Asano Magnús M. Halldórsson Kazuo Iwama Takeshi Matsuda Approximation Algorithms for the Maximum Power Consumption Problem on Combinatorial Circuits. 204-215 http://dx.doi.org/10.1007/3-540-40996-3_18 2000 conf/isaac/2000 ISAAC db/conf/isaac/isaac2000.html#AsanoHIM00