Seyed Amir Yahyavi Firouz Abadi Laleh Roostapoor Roohollah Aslanzadeh Mehdi Dehghan Nasser Yazdani Intrusion K-Coverage in Wireless Sensor Networks. 41-46 2008 WINSYS conf/winsys/2008 db/conf/winsys/winsys2008.html#AbadiRADY08