The link between head injuries and CTE in football, explained - Vox

49ers Chris Borland retires from football, citing concern over head injuries - Field Gulls

NFL's new quarterback specific helmet design – United Brain Association

Steve Jordan helps kick off study to find CTE in living people - Daily Norseman

University of Wisconsin football players downplay warnings while proof of brain injury — even from small hits — piles up - Wisconsin Watch

NFL's new quarterback specific helmet design – United Brain Association

Playing football is even worse for players' brains than we thought - Vox

NFL Players Twice as Likely to Get Concussions in Cold Weath

Study links youth football to greater risk of later health problems - The Boston Globe

Why the NFL can finally admit football causes CTE and not owe players anything

The Harmful Neurological Effects of Football on the Human Brain - Medical Journalism Club

CTE explained: What is the brain condition and what are the risks?, US News

Concussions in the NFL: Are players beginning to value their brains more than the game? - Behind the Steel Curtain