TY  - RPRT
TI  - Northern bobwhite, gray partridge, and ring-necked pheasant population trends (1966-1988) from the North American Breeding Bird Survey
AU  - Sam Droege
AU  - J.R. Sauer
PY  - 1990
UR  - https://pubs.usgs.gov/publication/5210631
ID  - 5210631
ER  -