I. Semkiv, H. Ilchuk, and N. Kashuba, Photoluminescence of Ag₈SnSe_{6 argyrodite}, Low Temp. Phys. 48, (2021) [Fiz. Nyzk. Temp. 48, 15-18, (2021)] DOI: https://doi.org/10.1063/10.0008957.