http://ftp.unitronics.com/e_Learning/Using%20GSM%20Modem_V4/
PLC - GSM MOBILE PHONE in AUTOMATED PARKING SYSTEM
http://video.search.yahoo.com/search/video;_ylt=A0oG7hXShbhMMYIAZP1XNyoA?ei=UTF-8&p=hoboken%20automated%20parking&fr2=tab-web&fr=yfp-t-701