A note on Krylov subspace methods for singular systems
\textit{D. Calvietti, B. Lewis} and \textit{L. Reichel} [Linear Algebra Appl. 316, No.~1-3, 157-169 (2000; Zbl 0963.65042)] studied the least-squares solution of a singular system of linear equations by using the so called range restricted GMRES method. The authors of this short paper found that one of the main results of the referred paper is incomplete. They present an example to show the incompleteness of the corresponding theorem and then give a modified result.
scientific article; zbMATH DE number 1790271