Claudio Bettini Sergio Mascetti Xiaoyang Sean Wang Dario Freni Sushil Jajodia Anonymity and Historical-Anonymity in Location-Based Services. 1-30 2009 Privacy in Location-Based Applications http://dx.doi.org/10.1007/978-3-642-03511-1_1 conf/esorics/2009-5599 db/conf/esorics/lncs5599.html#BettiniMWFJ09