@misc{indiciae597b4987923e,
  title = {Lower ionosphere at solar minimum.},
  author = {Aikin, A. C. and Bourdeau, R. E. and Donley, J. L.},
  year = {1966},
  url = {https://ntrs.nasa.gov/citations/19660041849},
  note = {Source identifier: 19660041849}
}