TY  - RPRT
TI  - Probabilistic and statistical relationships between number of vehicles and number of visitors at a geologic site in a National Park
AU  - R. A. Crovelli
PY  - 1997
DO  - 10.1007/bf02769624
UR  - https://pubs.usgs.gov/publication/70019279
ID  - 70019279
ER  -