Standard basis in the $T$-ideal formed by polynomial identities of triangular matrices

We give the definition of a standard basis of a $T$-ideal of the free associative algebra over a field of zero characteristic and indicate some basis called canonical in the linear space of $n$-linear forms. Using this basis, we construct a standard basis in the $T$-ideal of identities satisfied by the algebra of upper triangular $(n\times n)$-matrices.