Retired Uniform Numbers in the American League

Every MLB team's retired numbers

Bill Russell's No. 6 Joins Rare Class of Retired Jersey Numbers - The New York Times

History of retired numbers dates back to Lou Gehrig Day

Yankees Retired Numbers - Who Are The 22 Yankees Who Wore Them

Eagles Question of the Day: How do you feel about the team's unofficial retired jersey numbers? - Bleeding Green Nation

Next retired number for every MLB team

Every MLB team's retired numbers

New York Yankees retired Paul O'Neill's No. 21 jersey

Retired number - Wikipedia

All 32 NFL team's retired jersey numbers - ESPN - NFL Nation- ESPN

The reasons why the Lakers decided to retire Pau Gasol's shirt

Eagles Question of the Day: How do you feel about the team's unofficial retired jersey numbers? - Bleeding Green Nation

List of Major League Baseball retired numbers - Wikipedia

Derek Jeter's No. 2, Last of Yankees' Single Digits, to Be Retired - The New York Times