@misc{indiciaeb83747a57989,
  title = {A singularity free analytical solution of artificial satellite motion with drag},
  author = {Scheifele, G. and Mueller, A. C. and Starke, S. E.},
  year = {1977},
  url = {https://ntrs.nasa.gov/citations/19780007204},
  note = {Source identifier: 19780007204}
}