Can new technology help cut down on concussions? (video)
NFL Releases Concussion Data After Use of 'Guardian Caps' During Offseason - Sports Illustrated
NFL training camps: Guardian Cap players are wearing over helmets, why
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
Built By Data: NFL Helmet Innovation
NFL executive hints that Guardian Caps could eventually be worn in games, along with position-specific helmets
Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic