Didn't know our helmets used to look like Chicago Bears logo
The History of the Football Helmet - Brain Injury Law Center
Chicago Bears Draft History: A Look at Every Draft Class of All Time
The Battered Helmet – Chicago and Cook County Cemeteries
Winged football helmet - Wikipedia
Chicago Bears: Take a look back at a century of uniforms
Notre Dame's helmet through the years
The History of Football Helmets, Xenith