Remarks on the norming sets of ${\mathcal L}(^ml_{1}^n)$ and description of the norming sets of ${\mathcal L}(^3l_{1}^2)$

Let $n\in \mathbb{N}, n\geq 2.$ An element $x=(x_1, \ldots, x_n)\in E^n$ is called a {\em norming point} of $T\in {\mathcal L}(^n E)$ if $\|x_1\|=\cdots=\|x_n\|=1$ and$|T(x)|=\|T\|,$ where ${\mathcal denotes the space all continuous $n$-linear forms on $E.$For we define set} $T$
 \centerline{$\qopname\relax o{Norm}(T)=\Big\{(x_1, E^n: (x_1, x_n)~\mbox{is point of}~T\Big\}.$}
 By $i=(i_1,i_2,\ldots,i_m)$ denote multi-index. In this paper show following:
 \noi (a) $n, m\geq 2$ and let $l_1^n=\mathbb{R}^n$ with $l_1$-norm. $T=\big(a_{i}\big)_{1\leq i_k\leq n}\in L}(^ml_{1}^n)$ $\|T\|=1.$Define $S=\big(b_{i}\big)_{1\leq l_1^m)$ be such that $b_{i}=a_{i}$ if$|a_{i}|=1$ $b_{i}=1$ if$|a_{i}|<1.$
 $A=\{1, n\}\times \cdots\times\{1, n\}$ $M=\{i\in A: |a_{i}|<1\}.$Then,
 o{Norm}(T)=\bigcup_{(i_1, i_m)\in M}\Big\{\Big(\big(t_1^{(1)}, t_{{i_1}-1}^{(1)}, 0, t_{{i_1}+1}^{(1)}, t_{n}^{(1)}\big), \big(t_1^{(2)}, t_{n}^{(2)}\big), \big(t_1^{(m)}, t_{n}^{(m)}\big)\Big),$}
 \centerline{$\Big(\big(t_1^{(1)}, t_{{i_2}-1}^{(2)}, t_{{i_2}+1}^{(2)}, \big(t_1^{(3)}, t_{n}^{(3)}\big), t_{n}^{(m)}\big)\Big),\ldots$}
 \centerline{$\ldots, \Big(\big(t_1^{(1)}, \big(t_1^{(m-1)}, t_{n}^{(m-1)}\big), t_{{i_m}-1}^{(m)}, t_{{i_m}+1}^{(m)}, t_{n}^{(m)}\big)\Big)\colon$}
 \centerline{$ t_{n}^{(m)}\big)\Big)\in \qopname\relax o{Norm}(S)\Big\}.$}
 This statement extend results [9].
 (b) Using result (a), describe sets every L}(^3l_{1}^2).$