@Book{Krumbacher1907,
author  = "Krumbacher, Karl",
title   = "Ein serbisch-byzantinischer Verlobungsring",
year    = "1907",
address = "München",
series  = "Sitzungsberichte",
volume  = "1906,10",
url     = "https://publikationen.badw.de/de/007458916",
}