@misc{indiciae05f33ed5ee9f,
  title = {Optimization of step rockets by the discrete maximum principle.},
  author = {Fan, L.-T. and Hwang, C.-L. and Wang, C.-S.},
  year = {1965},
  url = {https://ntrs.nasa.gov/citations/19660034737},
  note = {Source identifier: 19660034737}
}