10 best NFL defenses of all time, ranked
When comparing the 2013 Seahawks and 1985 Bears, don't forget the 2000 Ravens
Broncos' defense thinks it's one of best ever after Super Bowl 50 win - Newsday
Statistical analysis of the greatest defenses in NFL history - Behind the Steel Curtain
Brandt: '85 Bears defense best ever
The 1985 Chicago Bears: The Greatest NFL Defense of all time — The Sporting Blog
The Ten Greatest NFL Defenses in the Super Bowl Era - Nick Deiuliis
Ranking the top five Super Bowl champion defenses ever: Steel Curtain vs. the '85 Bears
The Top 10 NFL Defenses of All Time, News, Scores, Highlights, Stats, and Rumors
NFL: The 20 Best Defenses in Football History Part I (Fewest Points Against, Single Season)
10 greatest defenses in Super Bowl history: From 1985 Bears to 2000 Ravens
Ronde Barber is in the Hall of Fame, and the legend of that Bucs defense grows again
The 20 best NFL teams from the 2000s