1. R.C. Obrien and W.B. James, “Nondestructive Evaluation and Quality Control,” ASM Handbook (Materials Park, OH: ASM, 1989), p. 536.
2. M.J. Johnson and J.R. Bowler, “Pulsed Eddy-Current Measurements for the Characterization of Thin Layers and Surface Treatments,” Review of Progress in Quantitative Nondestructive Evaluation (New York: Plenum Press, 1997), p. 251.
3. E.P. Papadakis and B.W. Peterson, “Ultrasonic Velocity as a Predictor of Density in Sintered Powder Metal Parts,” Materials Evaluation, (1979), p. 77.
4. D.J. Roth et al., “Review and Statistical Analysis of the Use of Ultrasonic Velocity for Estimating the Porosity Fraction in Polycrystalline Materials,” Review of Progress in Quantitative Nondestructive Evaluation (New York: Plenum Press, 1991), p. 1749.
5. M.O. Marloew and D.R. Wilder, “Sensitive Resonant Frequency Technique for the Study of Sintering Kinetics,” J. Amer. Cer. Soc., 50 (1967), p. 145.