@misc{indiciae7d1795f76864,
  title = {Techniques for evaluating long periodic orbit variations},
  author = {Douglas, B. C. and Klosko, S. M. and Williamson, R. G. and Marsh, J. G.},
  year = {1974},
  url = {https://ntrs.nasa.gov/citations/19750043037},
  note = {Source identifier: 19750043037}
}