Throwback: The truth about George Halas and the NFL's ban on black players - Windy City Gridiron
How old is former NFL coach Marv Levy? His dad was wounded in WWI
Osmanski's opening salvo lead to the NFL's most one-sided championship: Looking back at Chicago Bears great Bill Osmanski with his son, John Osmanski, Sr., of Galena
Hutson's loss in WWII Pro Football Hall of Fame
Halas, the Father of the NFL - Dawgs By Nature
Dick Butkus obituary, NFL
Throwback: The truth about George Halas and the NFL's ban on black players - Windy City Gridiron
NFL history: 100 people who shaped the league, pro football - Sports Illustrated
Football and the NFL During World War II