@book { Personalentwicklung,
    title = "Personalentwicklung",
    author = "Frederik Gregory {Pferdt}",
    year = "2001",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640029518",
    url = "https://www.hausarbeiten.de/document/104634"
}