NFL Puts Up $3 Million to Find Out Who Can Build a Better Helmet - Bloomberg
Virginia Tech Helmet Lab tests SAFR Helmet Covers, orders 110 for the VA Tech football team – SAFR Sports
Wearing headgear for sport does not protect against concussion, Australian experts warn, Concussion in sport
NFL retired players still have pending litigation against Riddell - Sports Illustrated
Riddell Sports and Concussion Litigation
Warning Labels on Helmets Combat Injury and Liability - The New York Times
Report warned Riddell that no helmet could prevent concussions but NFL's helmet-maker marketed one as such anyway - ESPN
Built By Data: NFL Helmet Innovation
Health and Safety Related Changes for the 2018 Season
Warning Label Decal For Football Helmets – Green Gridiron, Inc.
Guardian Caps Guardian Sports
NFL Helmet Manufacturer Warned On Concussion Risk
New helmet standard to address concussion prevention
Football helmet design can lower concussion risk, study finds