@book { DerWegzumCoachCoachingKompetenzWerdegngeErfolgskriterien,
    title = "Der Weg zum Coach: Coaching-Kompetenz, Werdegänge, Erfolgskriterien",
    author = "Mareen {Stein}",
    year = "2014",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/270475"
}