Football helmet joins fight vs. head injuries - The Boston Globe
Timeline: The NFL's Concussion Crisis, League of Denial: The NFL's Concussion Crisis, FRONTLINE
NFL Concussions: The 2012-13 Season In Review
Russell Gage's injury highlights the NFL's concussion problem and how it hurts players long-term
Awareness of football's concussion dangers goes back 100 years
Jovan Belcher lawsuit shows concussion deal didn't end NFL's problems
NFL Concussion Protocol After Miami Dolphins Quarterback Tua Tagovailoa - Bloomberg
FRONTLINE, League of Denial: The NFL's Concussion Crisis, Season 2013, Episode 16
NFL's handling of concussions questioned after Tua's injury
Giants looking to end two-game skid against Dolphins - The San Diego Union-Tribune
Roughing the passer gone wrong? Post Tua, the NFL is protecting QBs at all costs — but it comes at the expense of integrity. - The Boston Globe
Bennet Omalu, Concussions, and the NFL: How One Doctor Changed Football Forever
Garoppolo out of concussion protocol, will start when Raiders host Packers