Roberto Di Pietro Luigi V. Mancini Alessandro Mei Alessandro Panconesi Jaikumar Radhakrishnan Connectivity properties of secure wireless sensor networks. 53-58 2004 conf/sasn/2004 SASN http://doi.acm.org/10.1145/1029102.1029112 db/conf/sasn/sasn2004.html#PietroMMPR04