Erratum

In this version of this article that was originally published [1] there were errors:

1. In the online HTML version of the full text, there is an unexpected text “\fontsize8.56” inserted in Eq. (22) of Appendix 1.

2. In the PDF version of the full text, the first paragraph in the right column of Page 3 is overlapped by Eq. (2).

The publisher apologises for these errors.