1. Historical maps of land use in Puerto Rico in 1951
- Author(s):
- Helmer, Eileen H.; Córdova, Juan R.; Quiñones, Maya; Hubing, Nick
2. Historical woodland density of the conterminous United States, 1873
- Author(s):
- Liknes, Greg C.; Nelson, Mark D.; Kaisershot, Daniel J.
3. Geomorphology influences extent and composition of riparian plant communities at the watershed scale in central Nevada
- Author(s):
- Engelhardt, Blake M. ; Weisberg, Peter J.; Chambers, Jeanne C.
U.S. Department of Agriculture