@article{Nasiroglu:20111V,
  author = "Nasiroglu, Ilham  and  Slowikowska, Agnieszka  and  Kanbach, Gottfried  and  Schwarz, Robert  and  Schwope, Axel",
  title = "{The orbital ephemeris and emission states of HU Aqr observed with OPTIMA}",
  doi = "10.22323/1.108.0048",
  journal = "PoS",
  year = 2011,
  volume = "HTRA-IV",
  pages = "048"
}