NFL CMO Dr. Allen Sills explains importance of mandated guardian caps during training camp
Utah Football vs. BYU by Mills Publishing Sports - Issuu
Guardian Caps: Why some NFL players are wearing them in training camps
2012 Army Football Media Guide by Army West Point Athletics - Issuu
NFL agrees to pay $765M to settle concussion suits - The San Diego Union- Tribune
Guardian Caps: Why some NFL players are wearing them in training camps
EXPLAINER: NFL using helmet caps for player safety, research
2014 Northwestern State Football Media Guide by Northwestern State Athletics - Issuu
2019 Northwestern State Football Media Guide by Northwestern State Sports Information - Issuu
NFL history: 100 people who shaped the league, pro football - Sports Illustrated
Haynesworth again skips Redskins conditioning test - The San Diego Union- Tribune