A perturbation algorithm for the pointers of Franke–Gorini–Kossakowski–Lindblad–Sudarshan equation A. A. Andrianov, M. V. Ioffe, E. A. Izotova and O. O. Novikov Eur. Phys. J. Plus, 135 6 (2020) 531 Published online: 27 June 2020 DOI: 10.1140/epjp/s13360-020-00540-3