@book { DiehistoristischeInnenausstattungvonStApostelninKln,
    title = "Die historistische Innenausstattung von St. Aposteln in Köln",
    author = "Marion {Kleffner}",
    year = "2021",
    publisher = "Meidenbauer",
    address = ", Germany",
    url = "https://www.peterlang.com/document/1105816"
}