@Book{Mohrmann1917,
author  = "Mohrmann, Hans",
title   = "Die Minimalzahl der stationären Ebenen eines räumlichen Ovals",
year    = "1917",
address = "München",
series  = "Sitzungsberichte",
volume  = "1917,1",
url     = "https://publikationen.badw.de/de/003395549",
}