@misc{_[Barthel,,
 address={[s.l.]},
 howpublished={online},
 language={ger},
 title={[Barthel, Karl]},
 keywords={photography, studio portrait, portrait, men, bust, clothing, glasses, hairstyle, photographic print (black and white), gelatin silver print, physician, official, German, Wrocław, R 293/31},
}