@misc{indiciaec1059305b8a2,
  title = {A new generating principle for two-fixed-center orbits - Conic solutions.},
  author = {Altman, S. P. and Pistiner, J. S.},
  year = {1968},
  url = {https://ntrs.nasa.gov/citations/19680063325},
  note = {Source identifier: 19680063325}
}