NFL Releases Concussion Data After Use of 'Guardian Caps' During Offseason - Sports Illustrated
NFL: Concussions drop 50% with Guardian Caps : r/nfl
NFL data: Concussions up 18 percent in 2022
The Quest for a Better Football Helmet
FNF Coaches 2019 Player Safety by A.E. Engine - Issuu
Simon Rea OU Sport & Fitness Team Blog
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
2023 West Virginia University Football Guide by Joe Swan - Issuu