@book { GrndungskonzepteinesWellnesshotels,
    title = "Gründungskonzept eines Wellnesshotels",
    subtitle = "Fallstudie",
    author = "Alexander {Wendel}",
    year = "2022",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/1174120"
}