@inproceedings{Treves:2009aO,
  author = "Treves, Aldo",
  title = "{ESO VLT optical spectroscopy of BL Lac objects}",
  doi = "10.22323/1.063.0026",
  booktitle = "Proceedings of Workshop on Blazar Variability across the Electromagnetic Spectrum {\textemdash} PoS(BLAZARS2008)",
  year = 2009,
  volume = "063",
  pages = "026"
}