Marcel Pougin de la Maisonneuve was the husband of Elizabeth Marcotte, granddaughter of Charles Marcotte, the patron of Ingres. The Pougin de la Maisonneuves had a daughter, Marie-Louise, who married Claude Chevane. The Chevanes became custodians of a large part of the Marcotte family art collection (including a large number of portrait drawings by Ingres) after Elizabeth's death in 1939.
Bibliography
1958
Naef, Hans. "Ingres Portraits of the Marcotte Familty." The Art Bulletin XL (1958): 336-345.
1977
Naef, Hans. Die Bildniszeichnungern von J.-A.-D. Ingres 5 vols. Bern, 1977-1980: II:503-533