M. V. Vasnetsov, V. Y. Bazhenov, V. V. Ponevchinsky, D. O. Plutenko, A. D. Kudryavtseva, and N. V. Tcherniega, “Temporal Characteristics of Afterglow in Artificial Opal”, Ukr. J. Phys., vol. 61, no. 9, p. 795, Jan. 2019.