Lim, H. J., Kim, Y., Koo, G., Yang, S., Sohn, H., Bae, I. H. and Jang, J. H. (2016).
"Development and field application of a nonlinear ultrasonic modulation technique
for fatigue crack detection without reference data from an intact condition." Smart
Materials and Structures, Vol. 25, No. 9, 095055 (p. 14).