@book { WettbewerbsbeschrnkungeninderWasserversorgung,
    title = "Wettbewerbsbeschränkungen in der Wasserversorgung",
    author = "Simon {Zepf}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1136046"
}