Abiotic formation of O2 and O3 in high-CO2 terrestrial atmospheres A. Segura, V. S. Meadows, J. F. Kasting, D. Crisp and M. Cohen A&A, 472 2 (2007) 665-679 Published online: 09 July 2007 DOI: 10.1051/0004-6361:20066663