Guardian Caps Guardian Sports
Guardian Caps Guardian Sports
Football helmet - Wikipedia
Health issues in American football - Wikipedia
New Football Helmet Could Save the Sport
Big Changes To NFL Helmets Coming Soon? - Daily Norseman
The link between head injuries and CTE in football, explained - Vox
Concussion prevention: Q-collar can reduce brain injury - Sports Illustrated
New helmet design can deal with sports' twists and turns
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Football helmets are creating more problems than they solve
The First Plastic Football Helmet Often Broke on Impact - The Atlantic
Head Trauma in High School Football May Be More Complicated Than We Thought - Scientific American Blog Network
Research Reveals Limitations of Football Helmets Against TBI's
Report warned Riddell that no helmet could prevent concussions but NFL's helmet-maker marketed one as such anyway - ESPN