1. Bradley, M. K. and Droney, C. K. “Subsonic Ultra Green Aircraft Research: Phase I Final Report,” Contractor Report NASA/CR-2011-216847, NASA Langley Research Center, Hampton, VA, April 2011.
2. Bradley, M. K. and Droney, C. K. “Subsonic Ultra Green Aircraft Research: Phase II: N+4 Advanced Concept Development,” Contractor Report NASA/CR-2012-217556, NASA Langley Research Center, Hampton, VA, May 2012.
3. Bradley, M. K., Droney, C. K., and Allen, T. J. “Subsonic Ultra Green Aircraft Research Phase II: Truss Braced Wing Design Exploration,” Contractor Report NASA/CR-2015-218704/Volume I, NASA Langley Research Center, Hampton, VA, April 2015.