@book { FestschriftfrWilhelmWestenberger,
    title = "Festschrift für Wilhelm Westenberger",
    subtitle = "Zum 70. Geburtstag",
    author = "Fritz {Burgbacher}",
    year = "1974",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    url = "https://www.peterlang.com/document/1069459"
}