@book { WasIstLeben,
    title = "Was Ist Leben?",
    author = "Piet {van Spijk}",
    year = "2014",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    doi = "10.3726/978-3-0351-0712-8",
    url = "https://www.peterlang.com/document/1052950"
}