@misc{indiciaeb8ef5c654a2a,
  title = {Length of count period as a possible source of bias in estimating bird densities},
  author = {J. M. Scott and F. L. Ramsey},
  year = {1981},
  url = {https://pubs.usgs.gov/publication/5210255},
  note = {Source identifier: 5210255}
}