Li, Xianjuan; Liu, Qiaohua Preconditioners for indefinite least square problems based on incomplete hyperbolic modified Gram-Schmidt. (Chinese. English summary) Zbl 1274.65085 Commun. Appl. Math. Comput. 26, No. 1, 45-52 (2012). MSC: 65F08 65F20 65F50 PDFBibTeX XMLCite \textit{X. Li} and \textit{Q. Liu}, Commun. Appl. Math. Comput. 26, No. 1, 45--52 (2012; Zbl 1274.65085)
Liu, Qiaohua; Li, Xianjuan Preconditioned conjugate gradient methods for the solution of indefinite least squares problems. (English) Zbl 1230.65052 Calcolo 48, No. 3, 261-271 (2011). MSC: 65F20 65F08 65F22 PDFBibTeX XMLCite \textit{Q. Liu} and \textit{X. Li}, Calcolo 48, No. 3, 261--271 (2011; Zbl 1230.65052) Full Text: DOI