Keizersgracht 349 huis, Amsterdam Previous house Next house Residents in February 1941 Julius Ernst Masse 1890 - 1943 Sara Henriette Masse-Aron 1893 - 1943 Gerd Helmut Masse 1924 - 1943 Residents Erwin Fels 1902 - 1944 Frida Markus-Jacobsohn 1882 - 1943