http://www.nflevolution.com/article/how-does-nfl-use-eye-in-the-sky-chiefs-medical-staffers-explain-it?ref=0ap3000000407140
NFL Evolution: How Does NFL Use ‘Eye In The Sky’? Chiefs Medical Staffers Explain It
http://www.nflevolution.com/article/how-does-nfl-use-eye-in-the-sky-chiefs-medical-staffers-explain-it?ref=0ap3000000407140