@book { KonjunkturelleGesamtindikatoren,
    title = "Konjunkturelle Gesamtindikatoren",
    author = "Holger {Bahr}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1088977"
}