Tony Dungy, football experts explain what made 1972 Dolphins perfect
E:60 Perfect Machine an informative look at 1972 Miami Dolphins
Ranking the winningest coaches in NFL history – NBC Sports Boston
NFL playoffs: Matchups and the wild-card weekend schedule
Brady–Belichick era - Wikipedia
Packers May Find Lessons in Perfection From Two That Failed - The New York Times
For Patriots, 16-0 Could Be Forgotten, but Not 19-0 - The New York Times
NFL: The ultimate guide of essentials to get ready for Week 4
How final undefeated NFL team has finished each season – NBC Sports Philadelphia
Hall of Famer Nick Buoniconti dies at 78 - NBC Sports