@book { Zeitgeist,
    title = "Zeitgeist",
    author = "Nihat {Ülner} and Erkan {Zengin} and Onur {Yılmaz} and Sedat {Şahin}",
    year = "2019",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b16610",
    url = "https://www.peterlang.com/document/1111198"
}