It's overdue'; Giants, A's reps back minor-league unionization movement
MLB players' association trying to unionize minor leaguers
Minor-league baseball players unionize: Minor leaguers officially join MLBPA after authorization
MLB, Minor Leaguers Reach Tentative Deal on First-Ever Collective Bargaining Agreement - WSJ
M.L.B. Players Association Working to Unionize Minor Leaguers - The New York Times
MLB Prepared to Voluntarily Recognize Minor League Union - Bloomberg
Minor League Baseball Union: How a Group of Players Sprung a Union on MLB - Sports Illustrated
MLBPA gets more than 50 percent of minor-league players to sign on in favor of unionization
The Long Road To Unionizing Minor League Baseball - Boardroom
MLB says it is prepared to voluntarily accept minor league union
Demands grow for MLB to recognize minor league players union
Minor League Baseball Joins Union — HUMP DAY NEWS
Majority of minor league baseball players turn in union authorization cards, paving way for MLBPA membership - ESPN