@misc{indiciaeb534aba3c9aa,
  title = {A closed life-support system for space colonies},
  author = {Johnson, R. D. and Jebens, H. J. and Sweet, H. C.},
  year = {1977},
  url = {https://ntrs.nasa.gov/citations/19770064007},
  note = {Source identifier: 19770064007}
}