@book { DerewigeGartenkalenderBand9September,
    title = "Der ewige Gartenkalender - Band 9: September",
    author = "Christina {Zacker}",
    year = "2013",
    publisher = "dotbooks Verlag",
    address = "München, Deutschland",
    doi = "10.3239/9783955203337",
    url = "https://m.dotbooks.de/document/230520"
}