@inbook{fazio_helmken_rieke_weekes_1970, 
  title={A Lower Limit to the Magnetic Field in the Crab Nebula from Cosmic γ-Ray Experiments at 1011 eV}, 
  DOI={10.1007/978-94-010-3311-4_42}, 
  publisher={Springer Netherlands}, 
  author={Fazio and Helmken and Rieke and Weekes}, 
  year={1970}
  }