Thomas King Thomas Haenselmann Wolfgang Effelsberg Deployment, Calibration, and Measurement Factors for Position Errors in 802.11-Based Indoor Positioning Systems. 17-34 2007 conf/loca/2007 LoCA http://dx.doi.org/10.1007/978-3-540-75160-1_2 db/conf/loca/loca2007.html#KingHE07