In this paper, we give a short and simple proof of the recent result of Ceng et al. (Math Methods Oper Res 67(3):375–390, <CitationRef CitationID="CR1">2008</CitationRef>). Copyright Springer-Verlag 2011

The purpose of this paper is to show that the iterative scheme recently studied by Xu (J Glob Optim 36(1):115–125, <CitationRef CitationID="CR8">2006</CitationRef>) is the same as the one studied by Kamimura and Takahashi (J Approx Theory 106(2):226–240, <CitationRef CitationID="CR2">2000</CitationRef>) and to give a supplement to these results. With the new technique proposed...</citationref></citationref>