@book { DerEndometrioseRatgeber,
    title = "Der Endometriose-Ratgeber",
    author = "Dr. med. Wilfried {Hohenforst}",
    year = "2022",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/1273524"
}