@misc{indiciaeb7ccfcc3b227,
  title = {National geodetic satellite program, part 1},
  author = {Dunnell, C. A. and Ferriter, P. and Gebel, G. and Hopfield, H. S. and Schaefer, M. M. and Yionoulis, S. M.},
  year = {1977},
  url = {https://ntrs.nasa.gov/citations/19780003604},
  note = {Source identifier: 19780003604}
}