@book { DieVereinbarungvariablerZinsstzeinAGB,
    title = "Die Vereinbarung variabler Zinssätze in AGB",
    author = "Verena {Förster}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1135510"
}