Ryan Callahan retires, has 'no regrets' over Lightning and Rangers tenures - The Athletic
Ryan Callahan may be forced to retire from NHL due to injury
1980 U.S. Men's Hockey Team: Where Are They Now?
Ryan Callahan retires from NHL with degenerative back disease
Lightning's Ryan Callahan suffers career-ending back injury
Ryan Callahan diagnosed with degenerative back disease, advised to no longer play hockey - Raw Charge
Ryan Callahan's Best in-Game Moments as a New York Ranger, News, Scores, Highlights, Stats, and Rumors
Former Rangers captain Ryan Callahan diagnosed with degenerative back disease
Ryan Callahan diagnosed with degenerative back disease, placed on IR - Sports Illustrated
Ryan Callahan Diagnosed with Degenerative Back Disease
Former Tampa Bay Lightning, New York Rangers F Ryan Callahan retires
Q&A: Ryan Callahan talks Stanley Cup, Olympics, ESPN
Ryan Callahan should be the Lightning's 12th forward for the playoffs
Ryan Callahan may be forced to retire from NHL due to injury