Evaluation of the two-loop self-energy correction to the ground state energy of H-like ions to all orders in ZαV. A. Yerokhin, P. Indelicato and V. M. ShabaevEur. Phys. J. D, 25 3 (2003) 203-238DOI: https://doi.org/10.1140/epjd/e2003-00270-x