Dick Butkus, fearsome Hall of Fame Chicago Bears linebacker, dies at 80
1970 NFL season - Wikipedia
SI's Pro Football Covers of the 1970s - Sports Illustrated
A History of the NFL in 95 Objects: Artificial Turf - Sports Illustrated
Photos from the 1970 NFL Season - Sports Illustrated
1970s - Sports Illustrated Vault
Dick Butkus, fearsome Hall of Fame Chicago Bears linebacker, dies at 80
Photos from the 1970 NFL Season - Sports Illustrated
New-Age Sam Darnold Tries to Solve an Age-Old Jets Problem - The New York Times
Think Tom Brady is an ironman? George Blanda was still playing at 48, NFL
Dick Butkus, Chicago Bears legend and Hall of Famer, dies at 80 - Los Angeles Times
Photos from the 1970 NFL Season - Sports Illustrated