@Book{Egger1902,
author  = "Egger, Joseph Georg",
title   = "Der Bau der Orbitolinen und verwandter Formen. Eine Studie",
year    = "1902",
address = "München",
series  = "Abhandlungen",
volume  = "Bd. 21, Abth. 3 = [9]",
url     = "https://publikationen.badw.de/de/003071174",
}