@misc{indiciae6ea3790309aa,
  title = {The ER-55 projector for aerial mapping},
  author = {R.K. Bean},
  year = {1953},
  doi = {10.1126/science.118.3069.484},
  url = {https://pubs.usgs.gov/publication/70221523},
  note = {Source identifier: 70221523}
}