Reza Farivar Mirko Montanari Ellick Chan Roy H. Campbell An Automatic User Study Demo in Indoor Environments and Its Privacy Implications. 1-3 2009 PerCom http://dx.doi.org/10.1109/PERCOM.2009.4912797 conf/percom/2009 db/conf/percom/percom2009.html#FarivarMCC09