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Yu.G. Pogorelov and V.M. Loktev, Conventional and unconventional impurity effects in superconductors (Review Article): , Low Temp. Phys. 44, 1–28, (2018) [Fiz. Nizk. Temp. 44, 3-35, (2018)] DOI: https://doi.org/10.1063/1.5020892.