Every MLB team's retired numbers
St. Louis Cardinals: From Oz to McGee, 51 iconic uni numbers
Yankees' Unique Jersey Problem Could Lead to a Universal MLB Rule Change - Sports Illustrated
Uniform number (Major League Baseball) - Wikipedia
Listing the only 3 NBA teams to not retire a single player's jersey
Houston Astros - Wikipedia
Power of Derek Jeter's No. 2 - MLB's most productive jersey numbers
2020 MLB season: New 60-man roster rules explained - Bless You Boys
Predicting the Next Retired Number for Every Team - The Crawfish Boxes
Dave Stewart wore A's No. 34 with Rollie Fingers' blessing. Now both will have it retired