Research memorandum RM (series). E53L14. Vapor pressures and calculated heats of vaporization of concentrated nitric acid solutions in composition range 71 to 89 percent nitric acid, 7 to 20 percent nitrogen dioxide, 1 to 10 percent water, and in temperature range 10° to 60° C [with list of references]; by A. B. McKeown and Frank E. Belles.