Jean-Pierre Mangin is a French philatelist specialized in finding error in the design of postage stamps. He wrote a bilingual world guide of "Errors on stamps". Member of the French Académie de philatélie since 4 June 1994, he presides the European Academy of Philately for a 2000-2007 mandate. He currently writes a monthly column in French magazine "L'Écho de la timbrologie" about errors on stamps found by the readers. Wikipedia
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