Source: Pirates will sign 4 Negro Leagues stars to 'contracts' for Hall of Fame induction

Baseball Integration Timeline, by John Thorn

Johnny Hopp – Society for American Baseball Research

Baseball Hall of Fame induction: Alabama members

Don Mattingly on The Ballot for Possible Hall of Fame Induction

Highlights from the Pirates' inaugural Hall of Fame induction

Meet Alabama's members of the Baseball Hall of Fame

Negro Leaguers in the National Baseball Hall of Fame

Crossing the Color Barrier: Jackie Robinson and the Men Who Integrated Major League Baseball - LA84 Foundation

Negro League legends every baseball fan should know

Elliott 2022's most influential top 110 Canadians: Thomson, Anthopoulos, Romano, Rogers — Final update — Canadian Baseball Network

As Pirates honor inaugural 19-member Hall of Fame class, ceremony disrupted by protester