@inproceedings{Abdalla:2018H7,
  author = "Abdalla, Hassan  and  Böttcher, Markus",
  title = "{Why the universe is unexpectedly transparent to very high energy gamma rays}",
  doi = "10.22323/1.319.0028",
  booktitle = "Proceedings of 5th Annual Conference on High Energy Astrophysics in Southern Africa {\textemdash} PoS(HEASA2017)",
  year = 2018,
  volume = "319",
  pages = "028"
}