Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant L. R. Colaço, J. E. Gonzalez and R. F. L. Holanda Eur. Phys. J. C, 81 6 (2021) 533 Published online: 22 June 2021 DOI: 10.1140/epjc/s10052-021-09319-x