Padded helmet cover shows little protection for football players - Scope
NFL helmet safety testing results: Vicis ranks first again for its high-tech head protector – GeekWire
New Smart Helmet Could Spot Concussions in Real Time
The NFL's Helmet Tests Are Brainless
Everything you need to know about the NFL's helmet guidelines and restrictions - Canal Street Chronicles
NFL Testing Safer Helmets
Tom Brady's helmet model among those banned for 2018 - Sports Illustrated
EXPLAINER: NFL using helmet caps for player safety, research
Xenith recalls helmets once tested to be some of safest on market; various area schools may be affected
Helmet safety: Inside the complicated equipment industry - Sports Illustrated
NFL testing 3D printed helmets from Carbon, Peyton Manning excited
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
Virginia Tech research provides much-needed data, system for rating sports equipment - ESPN
Helmet Laboratory Testing Performance Results