Franck Sauvage - Doc Savage

By the end of the 1930's, translators changed the name of Doc Savage into Franck Sauvage. His stories were published in various youth mags such as Le Journal de Mickey, Robinson, Donald and Story (Belgium) under "Nouvelles aventures de Franck Sauvage" ou "D'autres aventures de Franck Sauvage". In 1939, 3 paperbacks were published (the third one wich I don't have is "La Vapeur du Néant") in Belgium in Collection "Aventures", using the original U.S pulp covers. The "author"(translator ?) is named as Guy d'Antin...