A note on the modified SOR method for Z-matrices

In this note, some errors in a recent article by Huang et al. [T.Z. Huang, G.H. Cheng, X.Y. Cheng, Modified SOR-type iterative method for Z-matrices, Appl. Math. Comput. 175 (2006) 258–268] are pointed out and new proofs for the corresponding results in Huang et al. are presented.