@book { KnowledgeforBusiness,
    title = "Knowledge for Business",
    author = "Stephan {Aerni} and Roland {Ferrari} and Hans {Rigert}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832443245",
    url = "https://m.diplom.de/document/219926"
}