Back numbers in football - meaning and history, Football shirt numbers and their meaning

The history of football squad numbers explained

The most iconic player to wear every shirt number

A history of rugby numbering systems – Squad Numbers

The strangest shirt numbers in football history

Why Soccer Numbers Matter - 3rd Degree

Soccer Player Jersey Numbers: Explained

Dominant Digits -- The 10 most popular jersey numbers among current NFL players - ESPN

The greatest players to wear each shirt number in football, including Lionel Messi no.10 and Cristiano Ronaldo no.7

What does each jersey number mean in soccer? – NBC Sports Chicago

Why do football clubs wear stars on their shirts, which European team wears the most stars and are they compulsory?

Squad number (association football) - Wikipedia