@book { WandelderPersonalentwicklunginderTouristikbranche,
    title = "Wandel der Personalentwicklung in der Touristikbranche",
    author = "Linda {Isenberg}",
    year = "2009",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836628181",
    url = "https://m.diplom.de/document/226705"
}