}D &:=& \left\{({{\mathbf{n}}},t)\in \N^0 \times R : \,n^a=0, \; 0\leq n^b < \infty, \; a \neq b\right\}\,, \\[0.0cm] \partial_{a+}D &:=& \left\{({{\mathbf{n}}},t)\in \N^0 \times R : \,n^a=M, \; 0\leq n^b < \infty, \; a \neq b\right\}\,, \\[0.0cm] && \lim\limits_{M\rightarrow \infty} \left[j_{..}^{b..}(