Water Polo rules book published in Paris, France by “éditions S.E.I.P.” in 1940: “Les règles de Water Polo conformes aux règles de la Fédération Française de Natation” – “Water Polo rules conforming with rules of the French swimming Federation”. Within the section ordinary fouls we notice: “Seront considérées comme fautes ordinaires: Partir avant le signal sifflé par l’ arbiter” – “Will be considered as ordinary fouls: Moving before the whistle of the referee”. In 1949, after London Olympics, the International Water Polo Board proposed the testing of the South American rules that were giving the possibility to the players to move after the whistling of the referees. This rule has been adopted in 1950 changing drastically the character of the game.
Source: Personal collection