Mario Zagalj Jean-Pierre Hubaux Christian C. Enz Minimum-energy broadcast in all-wireless networks: : NP-completeness and distribution issues. 172-182 2002 conf/mobicom/2002 MOBICOM http://doi.acm.org/10.1145/570645.570667 db/conf/mobicom/mobicom2002P.html#ZagaljHE02