@book { InnovativePreismodellefrhybrideProdukte,
    title = "Innovative Preismodelle für hybride Produkte",
    author = "Christoph {Da-Cruz}",
    year = "2007",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836604864",
    url = "https://m.diplom.de/document/225344"
}