@book { DerGrundrechtsschutzdernegativenVereinigungsfreiheit,
    title = "Der Grundrechtsschutz der negativen Vereinigungsfreiheit",
    author = "Wolf {Etzrodt}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1072298"
}