Has there ever been a successful coach-GM in NFL history? - Quora
NWH-10-1-2015 by Shaw Media - Issuu
RR Auction October 2012: Rare Manuscripts, Documents and Autographs by RR Auction - Issuu
Papa Bear' Halas honored with statue
Chicago Bears founder George Halas played a part in everything for NFL - Chicago Sun-Times
Throwback: The truth about George Halas and the NFL's ban on black players - Windy City Gridiron
Chicago Bears founder George Halas played a part in everything for NFL - Chicago Sun-Times
NFL History: 100 objects that tell the story of football - Sports Illustrated
Team History Pro Football Hall of Fame
Throwback: The truth about George Halas and the NFL's ban on black players - Windy City Gridiron