Ichitaro Yamazaki, Zhaojun Bai, Wenbin Chen and Richard Scalettar. (2009). A High-Quality Preconditioning Technique for Multi-Length-Scale Symmetric Positive Definite Linear Systems.
Numerical Mathematics: Theory, Methods and Applications. 2 (4).
469-484.
doi:10.4208/nmtma.2009.m9008s