Invitational Workshop on USDA Activities in Biological Control (1996 : Riverdale, Prince George's County, Md., and Washington, D.C.) (Riverdale, Prince George's County, Md.; Washington, D.C.)
sponsored by USDA Forest Service, Northeastern Forest Experiment Station, University of Vermont, School of Natural Resources ; edited by Margaret M. Harris, Ann M. Spearing
sponsored by USDA Forest Service, Northeastern Forest Experiment Station, University of Vermont, School of Natural Resources ; edited by Margaret M. Harris, Ann M. Spearing
sponsored by USDA Forest Service, Northeastern Forest Experiment Station, University of Vermont, School of Natural Resources ; edited by Margaret M. Harris, Ann M. Spearing