@book { DerWelteinZeichengeben,
    title = "Der Welt ein Zeichen geben",
    author = "Gebhard {Ottacher}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832450212",
    url = "https://m.diplom.de/document/220171"
}