Carlos Bento Teresa Soares Marco Veloso Bruno Baptista A Study on the Suitability of GSM Signatures for Indoor Location. 108-123 2007 conf/eusai/2007 AmI http://dx.doi.org/10.1007/978-3-540-76652-0_7 db/conf/eusai/ami2007.html#BentoSVB07