Ionut Cardei Mihaela Cardei Energy-efficient connected-coverage in wireless sensor networks. 201-210 2008 3 IJSNET 3 http://www.inderscience.com/search/index.php?action=record&rec_id=18484&prevQuery=&ps=10&m=or db/journals/ijsnet/ijsnet3.html#CardeiC08