@misc{indiciae31a3b0693bbd,
  title = {Fraunhofer line-depth sensing applied to water},
  author = {George Eimert Stoertz},
  year = {1969},
  doi = {10.3133/ofr69271},
  url = {https://pubs.usgs.gov/publication/ofr69271},
  note = {Source identifier: ofr69271}
}