MLB expands list of who can wear No. 21 to honor Roberto Clemente on Sept. 15 - ESPN

The Greatest Forgotten Home Run of All Time ‹ Literary Hub

Roberto Clemente day: Puerto Rican MLB players, Pirates wear No. 21

ESPN: MLB to allow Pirates, Puerto Rican players, award nominees to wear No. 21 on Roberto Clemente Day

Hispanic Heritage Month: Roberto Clemente tops list of baseball's legendary Latino faces - ESPN

Roberto Clemente's Puerto Rico Winter League Career, Part I – Society for American Baseball Research

Daily Sports Smile: 50 years after Roberto Clemente's death, MLB honors No. 21

Uniform number (Major League Baseball) - Wikipedia

Rays make history by starting MLB's first all-Latino lineup on Roberto Clemente Day

Tampa Bay Rays News & Links: Happy Roberto Clemente Day! - DRaysBay

Rivera] League source confirms league-wide retirement of Roberto Clemente's #21 is not happening at this time and there is no current plan in place for it to occur : r/baseball

MLB expands list of who can wear No. 21 to honor Roberto Clemente on Sept. 15 - ESPN

Major League Baseball marks Roberto Clemente Day with ceremony at Citi Field - ESPN

All of MLB's Puerto Rican players can wear No. 21 on Roberto Clemente Day