The Fruitless Search for a 'Concussion-Proof' Football Helmet - The Atlantic
Future of football safety could come down to research in Riddell's suburban Chicago office
Varsity Football Helmet Ratings
Varsity Football Helmet Ratings
New Riddell SpeedFlex football helmet pits technology vs. concussions
New Riddell SpeedFlex football helmet pits technology vs. concussions
How do football helmets help prevent concussions? - Quora
Football helmet with liquid padding may prevent concussions
Riddell Speedflex – The Next Generation Of Football Helmet – OSI Physical Therapy
Digital design, QB investments could aid football helmets