  Differrential Graded Lie Algebra Dg was previously introduced in the context
of current algebras. We show that under some conditions, the problem of
constructing equivariantly closed form from closed invariant form is reduces to
construction of a representation of Dg. This includes equivariant BV formalism.
In particular, an analogue of intertwiner between Weil and Cartan models allows
to clarify the general relation between integrated and unintegrated vertex
operators in string worldsheet theory.
