Yankees retired numbers: A look at all of the jersey numbers players cannot wear in the Bronx
Yankees Retired Numbers
New York Yankees retired Paul O'Neill's No. 21 jersey
Every NBA Team's Retired Numbers - Fadeaway World
Every NBA Team's Greatest Player Who Does Not Have Their Jersey Retired - Fadeaway World
History of retired numbers dates back to Lou Gehrig Day
Yankees Retired Numbers - Who Are The 22 Yankees Who Wore Them
Retired Jerseys - Army West Point
Last player to wear No. 42 for each MLB team
Jude Bellingham: Birmingham City Retire Number 22 Shirt After Transfer
Retired number - Wikipedia
History of retired numbers dates back to Lou Gehrig Day