Benedikt Gierlichs Carmela Troncoso Claudia Díaz Bart Preneel Ingrid Verbauwhede Revisiting a combinatorial approach toward measuring anonymity. 111-116 2008 WPES http://doi.acm.org/10.1145/1456403.1456422 conf/wpes/2008 db/conf/wpes/wpes2008.html#GierlichsTDPV08