NFL Players Association not happy with league's proposed wristband policy - The Boston Globe
JC Tretter: NFL would've canceled Browns-Raiders game if not for union
Former Browns, Packers center JC Tretter announces retirement after eight NFL seasons
Browns' JC Tretter, NFLPA president, pumps brakes on report of possible June minicamp
Former Browns center, NFLPA president JC Tretter retires
NFLPA president J.C. Tretter of Browns says league is working toward COVID-19 game plan – Morning Journal
Ravens Urged to Sign Ex-Browns, Packers Center JC Tretter
NFLPA president hammers NFL over plans to return to football - Pride Of Detroit
Browns center J.C. Tretter, the new NFLPA president, assessing 'long list of hurdles' for players - ESPN
Browns center, NFLPA president JC Tretter calls for end to NFL's offseason practices
The NFL cast JC Tretter out; the NFLPA president says that only makes him more powerful - Sports Illustrated
NFL call for grass instead of turf