@book { RckengesundheitNeueaktiveWege,
    title = "Rückengesundheit - Neue aktive Wege",
    author = "Klaus {Pfeifer}",
    year = "2020",
    publisher = "Deutscher Ärzteverlag",
    address = "Köln, Germany",
    doi = "10.47420/9783769137378",
    url = "https://deutscheraerzteverlag.openpublishing.com/document/945752"
}