Manolis Kritsotakis Maria Michou Emmanouil Nikoloudakis Antonis Bikakis Theodore Patkos Grigoris Antoniou Dimitris Plexousakis C-NGINE: A Contextual Navigation Guide for Indoor Environments. 258-275 2008 AmI http://dx.doi.org/10.1007/978-3-540-89617-3_17 conf/ami/2008 db/conf/ami/ami2008.html#KritsotakisMNBPAP08