Daniele Riboni Claudio Bettini Private context-aware recommendation of points of interest: An initial investigation. 584-589 2012 PerCom Workshops https://doi.org/10.1109/PerComW.2012.6197582 https://doi.ieeecomputersociety.org/10.1109/PerComW.2012.6197582 conf/percom/2012w db/conf/percom/percomw2012.html#RiboniB12