NFL Releases Concussion Data After Use of 'Guardian Caps' During Offseason - Sports Illustrated
Pregame: Illinois vs Toledo, Saturday, September 2nd, 6:30pm CT, BTN
NFL hopes to reduce head injuries with helmet experiment
What are Guardian Caps? Shadow Hills football using new device to reduce head injuries
Guardian Caps: NFL requires use of helmet cover at training camps to reduce head injuries
How a soft-shell helmet is limiting the risk of concussions at Rutgers football camp
NFL: Concussions dropped by more than 50% among players who wore Guardian Caps during summer
Football helmet - Wikipedia
Concussions among players who wore Guardian Caps over summer dropped more than 50%, NFL says - ESPN
Ohio State Aiming To Reduce Head Injuries With Guardian Caps - Sports Illustrated Ohio State Buckeyes News, Analysis and More
Guardian Cap used by football teams to protect against head injury – The Denver Post