Boston Red Sox to retire Pedro Martinez's number - ESPN
What should the Yankees do once they run out of numbers? - Pinstripe Alley
High and Tight: Our Rock & Roll Baseball Experts Talk Retired Numbers
If the Boston Red Sox retired numbers like the New York Yankees do - ESPN
New York Yankees to retire Paul O'Neill's No. 21 on Aug. 21
Numbers the Red Sox Should Consider Retiring - Over the Monster
A little group of collages I made featuring the most retired numbers in baseball : r/baseball
New York Yankees - Wikipedia
Yankees want to stop issuing jersey numbers to manager/coaches
All Red Sox retired numbers: Fenway legends
The New York Yankees Could Run Out of Jersey Numbers After Retiring Them - What Happens Next? - EssentiallySports
Yankees-Red Sox rivalry went from hatred to RE2PECT and back
New York Yankees: Retiring numbers, plaque ceremonies must end