NFL Players Experiment With 'Guardian Caps' to Protect Heads – NBC Connecticut
Guardian Caps: Why some NFL players are wearing them in training camps
Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
NFL players beginning to adopt protective Guardian Caps over helmets at practice - NBC Sports
NFL players experiment with 'Guardian Caps' to protect heads
PDF) Preliminary Examination of Guardian Cap Head Impact Data Using Instrumented Mouthguards
The potential solution to serious head injuries in football is counter-intuitive - Hogs Haven
Steelers Daily Links: More Lamar Jackson Drama; FA Grades
Coverage of the NFL in Guardian Caps
Guardian Caps: Why some NFL players are wearing them in training camps
NFL reports reduction in concussions among players who wore Guardian Caps in preseason - The Athletic
NFL hopes to reduce head injuries with helmet experiment
Guardian Caps Debut at Training Camps Across the NFL