@book { LernenundArbeiteninderInternetbungsfirmaYoungBusiness,
    title = "Lernen und Arbeiten in der Internet-Übungsfirma YoungBusiness",
    author = "Martin {Böllinger}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832432072",
    url = "https://m.diplom.de/document/218901"
}