@article{Chen:2016PL,
  author = "Chen, Songzhan  and  Vernetto, Silvia",
  title = "{4.5-year simultaneous multi-wavelength observation of Mrk 421 in ARGO-YBJ and Fermi overlap era }",
  doi = "10.22323/1.236.0705",
  journal = "PoS",
  year = 2016,
  volume = "ICRC2015",
  pages = "705"
}