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When translated into English for a publication by Methuen in 1963, a number of Francophone place-names were changed; for instance, the port of Saint-Nazaire was renamed Westermouth, which, according to author Michael Farr, was probably inspired by the real English coastal town of Weymouth. As the English-language translation was published after the English translation of other "Tintin" adventures, which had actually been authored later than "The Seven Crystal Balls", in the English version, references are made to events that would occur in "The Calculus Affair" and "The Red Sea Sharks".