@book { ControllingingesetzlichenKrankenversicherungen,
    title = "Controlling in gesetzlichen Krankenversicherungen",
    author = "Jörg Klaus {Hofmann}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1088168"
}