@misc{indiciae3ffa1f9cdc0b,
  title = {A trajectory optimization technique based upon the theory of the second variation},
  author = {Kelley, H. J. and Kopp, R. E. and Moyer, H. G.},
  year = {1964},
  url = {https://ntrs.nasa.gov/citations/19650026535},
  note = {Source identifier: 19650026535}
}