@Book{Damköhler1940,
author  = "Damköhler, Wilhelm",
title   = "Zur Frage der Äquivalenz indefiniter Variationsprobleme mit definiten",
year    = "1940",
address = "München",
series  = "Sitzungsberichte",
volume  = "1940,1",
url     = "https://publikationen.badw.de/en/003399362",
}