@misc{indiciae1fc4d383ec12,
  title = {Optimization of Low-Thrust Spiral Trajectories by Collocation},
  author = {Falck, Robert D. and Dankanich, John W.},
  year = {2012},
  url = {https://ntrs.nasa.gov/citations/20120014379},
  note = {Source identifier: 20120014379}
}