Frédéric Saly-Giocanti is a lecturer in contemporary history at the Gustave Eiffel University and a member of the ACP laboratory. He is in charge of the master’s degree in teaching, education and training in history. As a specialist in German history, he has worked on social mobility and migration in German cities in the 20th century. He has worked on nominative sources, but also on the German administrative statistical archives. He is a specialist in statistical data processing and map visualization. He is currently working on the population census of the Seine department in 1954 and on the IGN aerial photographs.