@book { DerewigeGartenkalenderBand5Mai,
    title = "Der ewige Gartenkalender - Band 5: Mai",
    author = "Christina {Zacker}",
    year = "2013",
    publisher = "dotbooks Verlag",
    address = "München, Deutschland",
    doi = "10.3239/9783955202118",
    url = "https://m.dotbooks.de/document/211202"
}