The future of football helmets is driven by innovation and a startup culture - The Athletic
Protecting Football Players' Brains - Big Compute
Helmets – The Concussion Blog
concussion - Lacrosse All Stars
Impact test comparisons of 20th and 21st century American football helmets in: Journal of Neurosurgery Volume 116 Issue 1 (2012) Journals
N.F.L. Acknowledges Long-Term Concussion Effects - The New York Times
Football helmet - Wikipedia
Accelerometers Could Finally Fix the NFL's Concussion Crisis
Concussions in American football - Wikipedia
Protecting Football Players' Brains - Big Compute
Football's future: Technology, rules changes will make the game safer - Sports Illustrated
Full article: Neurochemical cascade of concussion