1. American University, Research Faculty, Washington DC, USA
2. International Institute for Applied Systems Analysis, Laxenburg, Austria
3. Scienze e Tecnologie Agrarie, Ambientali e Forestali, Firenze, Italy
4. CNR IVALSA, Sesto Fiorentino, Italy
5. EX-Forest Service, Forest Products Laboratory, USA
6. Northern Arizona University, Forest Operations and Biomass Utilization, USA