TY  - RPRT
TI  - Population ecology of the mallard: II. Breeding habitat conditions, size of the breeding populations, and production indices
AU  - Richard S. Pospahala
AU  - David R. Anderson
AU  - Charles J. Henny
PY  - 1974
UR  - https://pubs.usgs.gov/publication/rp115
ID  - rp115
ER  -