Josep Balasch Alfredo Rial Carmela Troncoso Bart Preneel Ingrid Verbauwhede Christophe Geuens PrETP: Privacy-Preserving Electronic Toll Pricing. 63-78 2010 USENIX Security Symposium http://www.usenix.org/events/sec10/tech/full_papers/Balasch.pdf conf/uss/2010 db/conf/uss/uss2010.html#BalaschRTPVG10