1. Department of Archaeology, the Hebrew University of Jerusalem, Jerusalem, Israel
2. Department of Geological Engineering and Mining, Faculty of Environmental Sciences and Biochemistry, University of Castilla-La Mancha, Toledo, Spain
3. Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Burgos, Spain
4. Fundación Atapuerca, Ibeas de Juarros (Burgos), Spain
5. Sociedad Española de Espeleología y Ciencias del Karst, Fundación Gómez Pardo, Madrid, Spain
6. Human Evolution Research Center, University of California, Berkeley, CA, USA