NFL CMO Dr. Allen Sills explains importance of mandated guardian caps during training camp
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Unprecedented Rate Of Improvement Stimulated In Helmet Industry, New Standard Set For 'Top-Performing' Helmet Models Worn By NFL Players
Guardian Cap Results: “Exceeded Our Expectations”
The N.F.L. Struggles to Tackle Its Latest Problem: Tackling - The New York Times
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
NFL says positions wearing Guardian Caps saw 52% decrease in concussions - NBC Sports
Applied Sciences, Free Full-Text
How the NFL plans to play a season during the pandemic
Future of NFL safety: Inside Vicis' high-tech football helmet production facility in Seattle – GeekWire
NFL hopes to reduce head injuries with helmet experiment
EXPLAINER: NFL using helmet caps for player safety, research