@misc{indiciaec752fcca8a8f,
  title = {The decrease of Lake Chad as documented during twenty years of manned space flight},
  author = {Mohler, Robert R. J. and Helfert, Michael R. and Giardino, John R.},
  year = {1989},
  url = {https://ntrs.nasa.gov/citations/19890054063},
  note = {Source identifier: 19890054063}
}