\input amstex
A:\underbrace{\pmb{\hbox{R}}^n\times\pmb{\hbox{R}}^n\times \dots\times\pmb{\hbox{R}}^n }_\textrm{m-puta}\longrightarrow \pmb{\hbox{R}}^k
,
A\in L(\pmb{\hbox{R}}^n,\pmb{\hbox{R}}^n,\dots,\pmb{\hbox{R}}^n;\pmb{\hbox{R}}^k)
\bye