@article{UBHD-68177334,
  author={Fraija, Nissim and Hiriart, David},
  title={Long-term optical polarization variability and multiwavelength analysis of Blazar Mrk 421},
  year={2017},
  language={eng},
  issn={1538-4365},
  volume={232(2017) Artikel-Nummer 7},
  number={25 Seiten},
  note={Gesehen am 10.10.2017},
  journal={The astrophysical journal},
  doi={10.3847/1538-4365/aa82cc},
}
@incollection{UBHD-68177336,
  author={Fraija, Nissim and Hiriart, David},
  title={Long-term optical polarization variability and multiwavelength analysis of Blazar Mrk 421},
  year={2017},
  language={eng},
  note={Gesehen am 10.10.2017},
  booktitle={De.arxiv.org},
}