@misc{indiciaebec8770f06ee,
  title = {FFTFIL; a filtering program based on two-dimensional Fourier analysis of geophysical data},
  author = {T.G. Hildenbrand},
  year = {1983},
  doi = {10.3133/ofr83237},
  url = {https://pubs.usgs.gov/publication/ofr83237},
  note = {Source identifier: ofr83237}
}