1. Detection of methane in the atmosphere of Mars;Formisano;Science,2004
2. Astrobiology: the search for life beyond the Earth;Grady;Geology Today,2003
3. The astrobiology primer: an outline of general knowledge-version 1, 2006;Astrobiology,2006
4. Evidence from the Mars Express high resolution stereo camera for a frozen sea close to Mars’ equator;Murray;Nature,2005
5. Scenarios for the evolution of life on Mars;Schulze-Makuch;Journal of Geophysical Research (Planets),2005