@Book{Steinheil1867,
author  = "Steinheil, Carl August",
title   = "Ueber Berechnung optischer Construktionen",
year    = "1867",
address = "München",
series  = "Sitzungsberichte",
volume  = "1867,2,16",
url     = "https://publikationen.badw.de/en/003392953",
}