@book { Industriegtermarketing,
    title = "Industriegütermarketing",
    subtitle = "Grundlagen des Business-to-Business-Marketings",
    author = "Klaus {Backhaus} and Markus {Voeth}",
    year = "2014",
    publisher = "Vahlen",
    address = "München, Deutschland",
    url = "https://vahlen.openpublishing.com/document/1220912"
}