In February 1940, the Nazi invasion was expected to come in the spring to follow, and Doeblin decided to file his work on diffusions at the Académie des Sciences in Paris.
Noong Pebrero 1940, ang Nasi pagsalakay ay inaasahan na dumating sa tagsibol upang sundin, at Doeblin nagpasya na file kanyang trabaho sa diffusions sa Académie des Sciences sa Paris.