TY  - RPRT
TI  - Power of sign surveys to monitor population trend
AU  - Katherine C. Kendall
AU  - Lee H. Metzgar
AU  - David A. Patterson
AU  - Brian M. Steele
PY  - 1992
DO  - 10.2307/1941877
UR  - https://pubs.usgs.gov/publication/1008642
ID  - 1008642
ER  -