First-principles calculation of electric field gradients and hyperfine couplings in YBa2Cu3O7S. Renold, S. Pliberšek, E. P. Stoll, T. A. Claxton and P. F. MeierEur. Phys. J. B, 23 1 (2001) 3-15DOI: https://doi.org/10.1007/s100510170077