U.S. Department of Agriculture1. Visitor perceptions of wilderness recreation carrying capacity: Survey data from 1969
- Author(s):
- Stankey, George H.; Armatas, Christopher A.
2. Paired quality assurance and operational field data from the northern region of the U.S. Forest Inventory and Analysis program
- Author(s):
- Barnett, Charles J.; Young, Alexander R.
3. Urban tree database
- Author(s):
- McPherson, E. Gregory; van Doorn, Natalie S.; Peper, Paula J.