Yankee Retired Numbers: The All-Time Numerical Lineup of Yanks
Number 21 Continues to Remain Sacred to the New York Yankees
Yankee Stadium: Monument Park - Retired Numbers - Babe Rut…
Derek Jeter's No. 2, Last of Yankees' Single Digits, to Be Retired
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Zero single-digit numbers in the Bronx? Actually, there's still
Yankees retire Paul O'Neill's No. 21 jersey - NBC Sports
New York Yankees: 5 numbers that need to be un-retired
The case for retiring Graig Nettles' number - Pinstripe Alley
Here are the Yankees' 21 retired numbers
Paul O'Neill Number Retirement Raises Debate - Last Word On Baseball