NACA research memorandum RM (series). (National Advisory Committee for Aeronautics.) [Processed. No longer confidential.]. E56L06. Experimental investigation of 0.4 hub-tip diameter ratio axial-flow compressor inlet stage at transonic inlet relative Mach numbers: 4, Performance of tapered-tip rotor configuration with reset blade angles [with list of references]; by John C. Montgomery and Frederick Glaser.