WASET
    Elena B. Cherepetskaya and  Alexander A. Karabutov and  Natalia B. Podymova and  Ivan Sas,  Nonlinear Transformation of Laser Generated Ultrasonic Pulses in Geomaterials.   journal   = {International Journal of Physical and Mathematical Sciences}, [online]. World Academy of Science, Engineering and Technology.
    September 2015, vol. 106(10). 614 - 617
    [viewed 17 April 2024]. Available from: https://publications.waset.org/pdf/10002622.