1. 'See National Technical Information Service Document No. PB 032189 (Office of Scientific Research and Development Rep. No. 545). Copies are available at the U. S. Library of Congress under the NTIS number.
2. A. H. Shapiro,The Dynamics and Thermodynamics of Compressible Fluid Flow(Wiley, New York, 1953).
3. L. D. Landau and E. M. Lifshitz,Fluid Mechanics(Addison-Wesley, Reading, Mass., 1959).
4. A Fundamental Derivative in Gasdynamics