@misc{indiciaea29541041ced,
  title = {SYNTHESIS OF MINIMUM WEIGHT PROTON SHIELDS},
  author = {Celnik, J. and Krumbein, A. D. and Mittelman, P. S. and Nakache, F. and Troubetzkoy, E. S.},
  year = {1962},
  url = {https://ntrs.nasa.gov/citations/19630005278},
  note = {Source identifier: 19630005278}
}