@Book{Liebmann1912,
author  = "Liebmann, Heinrich",
title   = "Das Pentagramma mirificum und die nichteuklidischen Parallelen",
year    = "1912",
address = "München",
series  = "Sitzungsberichte",
volume  = "1912,12",
url     = "https://publikationen.badw.de/en/003395742",
}