@article{roeckel_1911, 
  title={Six Vocal Duets. For Medium Voices, with Pianoforte Accompaniment}, 
  volume={52}, 
  DOI={10.2307/907025}, 
  number={823}, 
  publisher={JSTOR}, 
  author={Roeckel}, 
  year={1911}, 
  month={Sep}
  }