head trauma
Punched out: The life and death of an NHL enforcer, Sports
Interview: John Branch, Author of 'Boy On Ice' : NPR
Hockey enforcers like Derek Boogaard die younger, study says - Axios Twin Cities
Punched out: The life and death of an NHL enforcer, Sports
The End of the NHL's Enforcer Era
Fall of the Boogeyman: Derek Boogaard's final days
Toronto Maple Leafs' GM Brian Burke on the enforcer's decline, waiving Colton Orr
Toughest Hockey Players in NHL History
Years after his son's death, Len Boogaard on quest to end fighting in hockey - The Globe and Mail
Rick Rypien - Wikipedia
Derek Boogaard: NHL Community Reactions to Rangers Enforcer's Passing, News, Scores, Highlights, Stats, and Rumors
The sad rise and fall of Derek Boogaard