Blackman, Calvin C.; White, H. Jack & Pragliola, Philip C. Flight and Test-Stand Investigation of High-Performance Fuels in Double-Row Radial Air-Cooled Engines 1: Determination of Cooling Characteristics of Flight Engine, report, December 20, 1944; (https://digital.library.unt.edu/ark:/67531/metadc62522/m1/1/: accessed April 23, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .