P. Neethling, T. T. Scheidt, E. Rohwer, H. von Bergmann, and H. Stafast, “Second harmonic generation as a technique to probe buried interfaces”, S. Afr. J. Sci., vol. 105, no. 7/8, Jan. 2010, Accessed: Apr. 19, 2025. [Online]. Available: https://sajs.co.za/article/view/10287