S. Dzhumanov, Sh. R. Malikov, and Sh. S. Djumanov, Pseudogap state and unusual metallic conductivity in high-T_c cuprate superconductors , Low Temp. Phys. 48, (2021) [Fiz. Nyzk. Temp. 48, 79-86, (2021)] DOI: https://doi.org/10.1063/10.0008967.