@book { DienstleistungsentwicklungimWellnessTourismus,
    title = "Dienstleistungsentwicklung im Wellness-Tourismus",
    author = "Markus {Bauer}",
    year = "2011",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842812079",
    url = "https://m.diplom.de/document/228411"
}