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Ecker, M., Botha, J., Lee-Thorp, J., Piuz, A., Horwitz, L., 2015. Ostrich eggshell as a source of Palaeoenvironmental information in the arid interior of South Africa: A case study from Wonderwerk Cave. Palaeoecology of Africa 33, 95-115. https://doi.org/10.1201/b19410-8. PDF