Philadelphia played an important role in the development of Black baseball

When Philly had a championship-winning Black baseball team: Remembering the Philadelphia Stars

Philadelphia Phillies, History & Notable Players

The Philadelphia Stars

Negro League Baseball, Black Community, and The Socio-Economic Impact of Integration – Society for American Baseball Research

Baseball Goes to War - Warfare History Network

Baseball (Professional) - Encyclopedia of Greater Philadelphia

Philadelphia A's: The greatest MLB team that history forgot - Sports Illustrated Vault

Negro Leagues exhibit at Cherry Street Pier tells stories of Philadelphia's baseball past

Philadelphia Phillies, History & Notable Players

Game times in Major League Baseball drop by an average of 24 minutes in first year of pitch clock - The Boston Globe

Why Was Oscar Charleston Forgotten?

Baseball Rights a Wrong by Adding Negro Leagues to Official Records - The New York Times

History of baseball in the United States - Wikipedia