National Football League (NFL), History, Teams, & Facts
The Birth of the National Football League
Chicago Bears - Wikipedia
How the NFL took over America in 100 years
Top 10 Facts About The NFL! - Fun Kids - the UK's children's radio
Official 2000 National Football League record & fact book
20+ National Football League Demographic And Financial Statistics
20 Football Facts: History, Popularity, Rules & More
2003 NFL Record & Fact Book, 84th Season Official National
NFL-National Football League Record Manual 1976-spiral bound
Official Site of the National Football League
National Football League - Wikipedia
NFL Football Teams - Official Sites of all 32 NFL Teams