@Book{Hofmann1867,
author  = "Hofmann, Konrad",
title   = "Zeugnisse über Berthold von Regensburg",
year    = "1867",
address = "",
series  = "Sitzungsberichte",
volume  = "1867,2,19",
url     = "https://publikationen.badw.de/de/003899495",
}