My starting point is to try and locate Café Lavenue. I have found a photograph, by chance, which suggests that it lay on a corner, an intersection somewhere along the Boulevard Montparnasse. The photograph shows where the street meets or is crossed by another street, and that there is a metro station in front. Lavenue looks to occupy the building, in typically grand Parisian style. I have a hunch that I may be able to locate the intersection and that the building itself may be unchanged.