Tak Wah Lam Lap-Kei Lee Hing-Fung Ting Isaac Kar-Keung To Prudence W. H. Wong Sleep with Guilt and Work Faster to Minimize Flow Plus Energy. 665-676 2009 ICALP (1) http://dx.doi.org/10.1007/978-3-642-02927-1_55 conf/icalp/2009-1 db/conf/icalp/icalp2009-1.html#LamLTTW09