Chris Borland retires from NFL aged 24
Respect for Chris Borland at Stanford pro day, but no change in players' resolve
49ers among biggest hit by early retirements of Borland, Anthony Davis, Willis
Chris Borland's early retirement shifts focus of head injuries in NFL - Los Angeles Times
Why the NFL needs to worry about Chris Borland
Expect more early NFL retirements, says former player
SF's Borland quits over safety issues - ABC7 San Francisco
He Gave Up MILLIONS…The Story of CHRIS BORLAND
49ers' Borland retires after rookie year over head trauma fears – Santa Cruz Sentinel
San Francisco 49ers linebacker Chris Borland retires due to health fears, NFL News
49ers' Chris Borland, 24, retires because of brain injury concerns - Los Angeles Times
Athlete to Educator: Chris Borland wants to talk
24-year-old NFL player quits over concussion worries