Electron impact excitation of Na-like Cu XIX using the Breit–Pauli R-matrix method Mayank Dimri, Dishu Dawra, A. K. Singh, Alok K. S. Jha, Rakesh Kumar Pandey, Rinku Sharma and Man Mohan Eur. Phys. J. D, 75 5 (2021) 157 Published online: 18 May 2021 DOI: 10.1140/epjd/s10053-021-00157-w