↑ a b c d e f g h i «Interpretation of the laws of the game and guidelines for referees: Law 4 – The Players’ Equipment». ↑ Erik Kirschbaum (8 de noviembre de 2005). «How Adidas and Puma were born». ↑ Soar, Phil (1983). «The Game in Scotland». ↑ «Record price for Pele’s shirt».…