@book { DieRechtmigkeitdesSympathiestreiks,
    title = "Die Rechtmäßigkeit des Sympathiestreiks",
    author = "Peter {Gumnior}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1103394"
}