Where was Louis de branges de bourcia born?

Louis de Branges was born in the American Hospital of Neuilly-sur-Seine on August 21, 1932, at a time when his parents had an apartment in the Square du Roule, Paris. The above statement was written by himself in the preface of his mothers book "Wartime Experiences 1939-1941". I am his sister's husband and --in case of any further questions-- can be reached by e-mail: rolfkueppers@aol.com