1. Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università di Bologna, Bologna, Italy.
2. Department of Geology, University of Johannesburg, Johannesburg, South Africa.
3. Centro de Astrobiologia and Instituto Nacional de Técnica Aeroespacial, Madrid, Spain.
4. School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes, United Kingdom.
5. Int'l Research School of Planetary Sciences, Università d'Annunzio, Chieti Scalo, Italy.
6. Jocobs University, Bremen, Germany.
7. CNRS Centre de Biophysique Moléculaire, Orléans, France.
8. Department of Earth and Environmental Sciences, Rutgers University, Newark, New Jersey, USA.
9. Department of Earth Sciences, Mekelle University, Mekelle, Ethiopia.