@book { SexualittimAlter,
    title = "Sexualität im Alter",
    author = "Erich {Grond}",
    year = "2011",
    publisher = "Schlütersche Verlagsgesellschaft mbH & Co. KG",
    address = ", Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403583"
}