t $$\begin{aligned} {\it l}_u\,\mathfrak{U} &=& T\,{\it l}_u\mathfrak{s} +E\wedge{\it l}_u P +B\wedge{\it l}_u M\nonumber\\ &&+{\Sigma _{\alpha}}_{\bot}^{\rm matt}\wedge{\it l}_u\underline{\vartheta}^\alpha -\underline{\Sigma}^{\rm matt}_\alpha\,{\it l}_u u^\alpha\