1. Rathbun, F. O. Jr., “Metal-To-Metal and Metal Gasketed Seals,” SAE Paper 650312, Aerospace Fluid Power Systems and Equipment Conference, Los Angeles, 1965, p. 156.
2. Wentworth, J. W. “A New Exhaust Pipe Sampling Valve,” General Motors Research Publication, GMR - 766, 1968.
3. Muller H. and vonWatzdorf S., “The Hydrocarbon Concentration near the Combustion-Chamber Wall after Combustion,” M. T. Z., 1968, Vol. 29, No. 12, Braunchweig, Germany.
4. Alperstein M. and Bradow, R. L. “Combustion Gas Sampling Valve,” The Review of Scientific Instruments, Vol. 36, No. 7, 1965.
5. Christensen, V. Mortensen, A. and Qvale, B. “The Development of a High-Speed Gas Sampling Valve For IC Engines,” DTH Laboratory for Energiteknik, Lyngby, Denmark, 1973, RE 73-1.