Panfilov, Y. V., M. I. Samoylovich, and E. V. Bulygina. “Deposition of Thin Films in Vacuum on Synthetic Opal Substrates”. Technology and Design in Electronic Equipment, no. 2, Apr. 2005, pp. 49-52, https://www.tkea.com.ua/index.php/journal/article/view/TKEA2005.2.49.