Oliver Jorns Gerald Quirchmayr Oliver Jung A Privacy Enhancing Mechanism based on Pseudonyms for Identity Protection in Location-Based Services. 133-142 2007 ACSW Frontiers http://crpit.com/abstracts/CRPITV68Jorns.html conf/acsw/2007 db/conf/acsw/acsw2007.html#JornsQJ07