TY  - RPRT
TI  - Towards a biological survey of the U.S. National Parks System
AU  - M. Ruggiero
AU  - T.J. Stohlgren
AU  - G. Waggoner
PY  - 1992
UR  - https://pubs.usgs.gov/publication/70126956
ID  - 70126956
ER  -