TY  - RPRT
TI  - Travel time variation on backcountry trails
AU  - J. W. van Wagtendonk
AU  - J.M. Benedict
PY  - 2018
DO  - 10.1080/00222216.1980.11969429
UR  - https://pubs.usgs.gov/publication/1007466
ID  - 1007466
ER  -