@book { HandbuchDienstleistungsmanagement,
    title = "Handbuch Dienstleistungsmanagement",
    author = "Hans {Corsten} and Stefan {Roth}",
    year = "2016",
    publisher = "Vahlen",
    address = "München, Deutschland",
    url = "https://vahlen.openpublishing.com/document/1221273"
}