  It has been shown that given a classical background in string theory which is
independent of $d$ of the space-time coordinates, we can generate other
classical backgrounds by $O(d)\otimes O(d)$ transformation on the solution. We
study the effect of this transformation on the known black $p$-brane solutions
in string theory, and show how these transformations produce new classical
solutions labelled by extra continuous parameters and containing background
antisymmetric tensor field.
