@Book{Reber1893,
author  = "Reber, Franz von",
title   = "Der karolingische Palastbau. Der Palast zu Aachen",
year    = "1893",
address = "München",
series  = "Abhandlungen",
volume  = "20,3",
url     = "https://publikationen.badw.de/de/003833955",
}