@book { BestimmungsfaktorenderVertragsforschunginDeutschland,
    title = "Bestimmungsfaktoren der Vertragsforschung in Deutschland",
    author = "Katarzyna {Haverkamp}",
    year = "2018",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b14158",
    url = "https://www.peterlang.com/document/1068649"
}