49ers' Chris Borland Retires From NFL Over Safety Concerns
Big Ten Leaders: Spring Wrap-Up
Chris Borland to retire from NFL, fearing concussions
San Francisco 49ers Linebacker Retires at 24 Over Head-Trauma Fears
Another San Francisco 49ers player retires, Chris Borland retires due to safety concerns
Chris Borland finding life after football isn't easy
Chris Borland, Fearing for Health, Retires From the 49ers. At 24. - The New York Times
Retiring 49er Chris Borland to pay back NFL signing bonus - Sports Illustrated
Chris Borland's early NFL retirement has led to impact off the field - BVM Sports
First-game flaws too familiar for 49ers
Chris Borland Headshot - LA84 Foundation
PDF) I Dont Think Its Worth the Risk: Media Framing of the Chris Borland Retirement in Digital and Print Media
NFL player's retirement at 24 prompts new debate about football concussions - The Washington Post