Farringer, Jerald, author.
Denver, CO : U.S. Department of the Interior, Bureau of Land Management, National Applied Resource Sciences Center, 2000.
2000
Egan, Thomas B., author.
Denver, CO : U.S. Department of the Interior, Bureau of Land Management, National Applied Resource Sciences Center, 2000.
2000
[Washington, DC (3501 New York Ave., NE., Washington 20002) : U.S. National Arboretum, U.S. Dept. of Agriculture, Agricultural Research Service, 2003]
2003