1. Presentation before the Ann. Cong. of the Hermann Oberth Gesellschaft;Ehricke,1976
2. Geolunar industrial transportation for low propellant expenditure with new energy management concepts for lunar access;Ehricke,1979
3. Program Results;Surveyor;NASA SP-184,1969
4. The lunar regolith as sampled by Apollo 11 and 12: Grain size, model analyses, origin of particles;King;Geochim. Cosmochim. Acta,1971