1 Retraction Note to: Bull. Malays. Math. Sci. Soc. (2017) 40:1781–1790 https://doi.org/10.1007/s40840-016-0385-4

The authors have retracted this article because the article contains major flaws in the proof of the main results. The results of the paper are invalid, since the assumption that the functionals considered are rotationally invariant is not valid. All authors have agreed to this retraction.