1. Cornell Tree Ring Laboratory, Department of Classics, B-48 Goldwin Smith Hall, Cornell University, Ithaca, NY 14853, USA.
2. Institute of Environmental Physics, University of Heidelberg, D-69120 Heidelberg, Germany.
3. Dipartimento di Scienze della Terra “Ardito Desio,” Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milano, Italy.
4. Centre for Isotope Research, Faculty of Science and Engineering, University of Groningen, Nijenborgh 6, NL-9747 AG Groningen, Netherlands.
5. Curt-Engelhorn-Center Archaeometry gGmbH, 68159 Mannheim, Germany.
6. Center for Applied Isotope Studies, University of Georgia, 120 Riverbend Rd., Athens, GA 30602, USA.