Dunhuang manuscripts
He was appointed to the Chair of "History and Philosophy of Mediaeval China" at the École Pratique des Hautes Études (EPHE), where he directed the Joint EPHE-CNRS Research Group working on the Dunhuang manuscripts from 1973 to 1985. His most important work was the completion and publication of the catalogue of the explorer Paul Pelliot's collection of Dunhuang manuscripts at the Bibliothèque nationale de France (French National Library). The Group also prepared descriptive notes to accompany the Pelliot collection of Chinese pictures at the Musée Guimet in Paris.