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2. ESA, “Terrae Novae 2030 + Strategy Roadmap” (2022).
3. NASA, “Moon-to-Mars Architecture Definition Document (ESDMD-001)” (National Aeronautics and Space Administration, 2023).
4. The scientific case for human space exploration;Astron. Geophys,2005
5. The scientific case for human space exploration;Space Policy,2001