@misc{_[Hardenberg,
 address={Berlin},
 howpublished={online},
 publisher={Hel. u. Impr. Meisenbach Riffarth & Co, Berlin},
 language={ger},
 title={[Hardenberg Karl August, Fürst von]},
 keywords={portrait, three-quarters- length, man, German graphics, Hardenberg, Karl August von (książę ; 1750-1822), https://viaf.org/viaf/4975077, Kinson Francois Josephe (1770/1774-1839), malarz flam., 20 w., 20. Jh., 20 century, Misenbach-Riffarth & Co. Berlin, https://viaf.org/viaf/147207304},
}