Riddell launches Axiom, latest helmet to combat concussions
APEX helmet designed to protect players
NFL Helmet Manufacturer Warned On Concussion Risk
Seeking to reduce head contact, NFL mandates use of Guardian Cap helmet for early portion of training camp - ESPN
New Riddell SpeedFlex football helmet pits technology vs. concussions
The First Plastic Football Helmet Often Broke on Impact - The Atlantic
How Engineers Are Making Football Helmets Safer
Helmet maker Riddell scores another touchdown in ex-students' concussion lawsuit
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
NFL hopes to reduce head injuries with helmet experiment
Football helmet with liquid padding may prevent concussions
13 NFL teams introduce alternate helmet looks for 2022 season
Football safety concerns come to a head – Orange County Register
Football helmets are creating more problems than they solve
Does price mean more protection when it comes to football helmets? New study says no - High School Football America