TY  - RPRT
TI  - Age determination of mallards
AU  - Gary L. Krapu
AU  - Douglas H. Johnson
AU  - C.W. Dane
PY  - 1979
DO  - 10.2307/3800347
UR  - https://pubs.usgs.gov/publication/1001538
ID  - 1001538
ER  -