Pirates bring back script on new uniforms - Uniform Authority
Sources: MLB letting more players to wear No. 21 for Clemente Day
Pirates to wear Roberto Clemente's number on Sept. 9 - Uniform Authority
Members of Red Sox wear No. 21 with pride on Roberto Clemente Day - The Boston Globe
Pirates to wear No. 21 on Sept. 9 to honor Roberto Clemente - NBC Sports
For the 'Great One'; Pirates, MLB honor Roberto Clemente –
Pirates' April matches club history despite loss to Nationals
Pirates' catcher Roberto Perez to have surgery, out for season, Pirates
How a collector in Florida wound up with Roberto Clemente's most iconic bat, National Sports
MLB expands list of who can wear No. 21 to honor Roberto Clemente on Sept. 15 - ESPN