TY  - RPRT
TI  - Colonial bird monitoring: A strategy for regional and national evaluation
AU  - R.M. Erwin
AU  - P.H. Geissler
AU  - M.L. Shaffer
AU  - D.A. McCrimmon
PY  - 1984
UR  - https://pubs.usgs.gov/publication/5210358
ID  - 5210358
ER  -