Praseodymium valency from crystal structure in Pr-Ba-Cu-O and (Y-Pr)-Ba-Cu-O single crystals G. Collin, P.A. Albouy, P. Monod et M. RibaultJ. Phys. France, 51 11 (1990) 1163-1177DOI: https://doi.org/10.1051/jphys:0199000510110116300
