TY  - RPRT
TI  - Elk, beaver, and the persistence of willows in national parks: Response to Keigley (1999)
AU  - F. J. Singer
AU  - L. C. Zeigenfuss
AU  - R.G. Cates
AU  - D.T. Barnett
PY  - 2000
UR  - https://pubs.usgs.gov/publication/1015074
ID  - 1015074
ER  -