Jean Gattefossé (1899-1960) was an advocate of a North African Atlantis and wrote two books on the subject. Earlier Gattefossé together with Claudius Roux published an extensive bibliography in a volume, which contains a list of 1,700 books and articles relating to Atlantis.
>In 1939, Gattefossé published a novel, Les Portes de Bronze  (The Bronze Doors), which purported to be based on the research notes of a then recently deceased ‘Jean de Sauveclare’, who had purportedly searched for Atlantis in 1921. Although de Sauveclare is noted on the cover as a co-author, I can find no record of any such real person – perhaps it was just a marketing ploy?<
According to Atlantisforschung.de(a) Gattefossé wrote to Egerton Sykes in 1959 declaring his belief that the Pillars of Heracles were situated in Tartessos now known as Seville, “where they are a tourist attraction.” The same link has interesting additional information about Jean and his brother René-Maurice.
(a) https://atlantisforschung.de/index.php?title=Jean_und_Ren%C3%A9-Maurice_Gattefoss%C3%A9 (German)