Class of 2019 Finalists Pro Football Hall of Fame
Pro Football Hall of Famer Dick Butkus dead at 80
Chicago Bears founder George Halas played a part in everything for NFL - Chicago Sun-Times
George Halas (2018) - Rose Bowl Hall of Fame - Tournament of Roses - Rose Bowl Game
American football – Travel guide at Wikivoyage
George Halas, Randall McDaniel, Pop Warner and Vince Young to be Inducted into the Rose Bowl Hall of Fame Class of 2018 - Tournament of Roses - Rose Bowl Game
NFL 100: At No. 84, Mel Hein, the Giants' 'absolutely outstanding' two-way menace - The Athletic
Pro Football Hall of Famer Dick Butkus dead at 80
George Halas – Society for American Baseball Research