A note on “Measuring propagation speed of Coulomb fields” by R. de Sangro, G. Finocchiaro, P. Patteri, M. Piccolo, G. PizzellaD. M. Gitman, A. E. Shabad and A. A. ShishmarevEur. Phys. J. C, 76 5 (2016) 261DOI: https://doi.org/10.1140/epjc/s10052-016-4108-7