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>

A uniqueness theorem of supporting hyperplanes for a class of convex level sets in a Hilbert space is obtained. As an application of this result, we prove an alternative theorem on solutions of variational inequalities defined on convex level sets. Three examples are given to demonstrate the...