@book { DieunbezifferteForderungsklage,
    title = "Die unbezifferte Forderungsklage",
    author = "Bahar Tuna {Kurtoglu}",
    year = "2019",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b15224",
    url = "https://www.peterlang.com/document/1057946"
}