Moore P B , Sen Gupta P K , Le Page Y , American Mineralogist , 74 (1989) p.1186-1194, Magnetoplumbite, PbFe12O19: Refinement and lone-pair splitting, Note: Symmetry constraints on U(i,j) for Fe5, O4 and O5 were incorrect,, and likely were refined wrong., They have been replaced with their isotropic equivalents.