Lucio Studer FerreiraMartijn KuipersCarlos RodriguesLuís M. CorreiaCharacterisation of Signal Penetration into Buildings for GSM and UMTS.63-672006ISWCShttps://doi.org/10.1109/ISWCS.2006.4362260conf/iswcs/2006db/conf/iswcs/iswcs2006.html#FerreiraKRC06