TY  - RPRT
TI  - Goose counts from aerial photographs using an optical digitizer
AU  - D.S. Gilmer
AU  - J.A. Brass
AU  - L.L. Strong
AU  - D.H. Card
PY  - 1988
UR  - https://pubs.usgs.gov/publication/1001659
ID  - 1001659
ER  -