1. Space Technology;J. H. Irving,1959
2. Ross, S., andLeitmann, G.,Low Acceleration Trajectory Optimization in a Strong Central Force Field, Proceedings of the IAS Symposium on Vehicle Systems Optimization, New York, New York, pp. 127–131, 1961.
3. Edelbaum, T. N.,The Use of High and Low-Thrust Propulsion in Combination for Space Missions, Journal of the Astronautical Sciences, Vol. 9, pp. 49–60, 1961.
4. Saltzer, C., andFetheroff, C. W.,A Direct Variational Method for Calculation of Optimum Thrust Programs for Power-Limited Interplanetary Flight, Astronautica Acta, Vol. 7, pp. 8–20, 1961.
5. Melbourne, W. G.,Three-Dimensional Optimum Thrust Trajectories for Power-Limited Propulsion Systems, ARS Journal, Vol. 31, pp. 1723–1728, 1961.