NFL's Decision to Ban Riddell VSR-4 and Schutt Air Advantage
Helmet hits causing more than just concussions - The Boston Globe
EXPLAINER: NFL using helmet caps for player safety, research
Guardian Cap Debuts at Training Camps League-wide
New Schutt Helmet: Vengeance (Rev.) – The Concussion Blog
Ratings for flag football headgear shape expectations for safety
NFL hopes to reduce head injuries with helmet experiment
Head Injuries & American Football - Ethics Unwrapped
What Pros Wear: Top 5 Helmets Rated by the NFL & NFLPA - What Pros
NFL hopes to reduce head injuries with helmet experiment
NFL Presents: League-wide Guardian Cap Use to Reduce Head Impacts
Biomechanics, Free Full-Text
NFL Testing Safer Helmets