1. Swedish University of Agricultural Sciences; Southern Swedish Forest Research Center; P.O. Box 49 SE-230 53 Alnarp Sweden
2. Johann Heinrich von Thünen-Institut (TI), Federal Research Institute for Rural Areas, Forestry and Fisheries; Institute of Forest Ecosystems; Alfred-Möller-Straße 1 D-16225 Eberswalde Germany
3. Hardwood Tree Improvement and Regeneration Center, Department of Forestry and Natural Resources; Purdue University; 715 W State Street West Lafayette IN 47907-2061 U.S.A.
4. Oak Ridge National Laboratory; Climate Change Science Institute; One Bethel Valley Road, P.O. Box 2800, MS6301 Oak Ridge TN 37831-6301 U.S.A.