@book { WirkungenvonAnreizsystemenimDeutschenJudosport,
    title = "Wirkungen von Anreizsystemen im Deutschen Judosport",
    author = "Philipp {Volkmer}",
    year = "2011",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656034070",
    url = "https://www.hausarbeiten.de/document/180581"
}