@misc{Hettner_Hermann_Julius_Theodor_[Korespondencja,
 author={Hettner, Hermann Julius Theodor},
 address={Heidelberg},
 howpublished={online},
 language={ger},
 title={[Korespondencja Friedricha Haasego - Haase 457]},
 type={text},
 keywords={Enrich Europeana Plus, correspondence},
}