@misc{indiciae665e62acc44f,
  title = {Factors influencing waterfowl counts on aerial surveys, 1961-66},
  author = {R. K. Martinson and C.F. Kaczynski},
  year = {1967},
  url = {https://pubs.usgs.gov/publication/5230045},
  note = {Source identifier: 5230045}
}