Relativistic density operators: Dirac dynamics, open quantum systems and non-standard neutrino interactionsA. S. Rosado González, J. I. Castro-Alatorre and E. SadurníEur. Phys. J. Plus, 137 8 (2022) 917DOI: https://doi.org/10.1140/epjp/s13360-022-03111-w