Aphrodite Tsalgatidou Jari Veijalainen Jouni Markkula Artem Katasonov Stathes Hadjiefthymiades Mobile E-Commerce and Location-Based Services: Technology and Requirements. 1-14 2003 conf/scangis/2003 ScanGIS http://www.scangis.org/scangis2003/papers/27.pdf db/conf/scangis/scangis2003.html#TsalgatidouVMKH03