@book { EsistdochnurWasser,
    title = "Es ist doch nur Wasser",
    author = "Sonja {Lülf}",
    year = "2004",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832478292",
    url = "https://m.diplom.de/document/223087"
}