@book { MotivationVonderGruppezumTeam,
    title = "Motivation - Von der Gruppe zum Team",
    author = "Jens {Magenheimer}",
    year = "2009",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640299508",
    url = "https://www.hausarbeiten.de/document/124918"
}