@book { CollectiveGovernanceinTarifverbnden,
    title = "Collective Governance in Tarifverbänden",
    author = "Achim {Engel}",
    year = "2015",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-05597-9",
    url = "https://www.peterlang.com/document/1049183"
}