  The coupling of Yang-Mills fields to the heterotic string in bosonic
formulation is generalized to extended objects of higher dimension (p-branes).
For odd p, the Bianchi identities obeyed by the field strengths of the
(p+1)-forms receive Chern-Simons corrections which, in the case of the 5-brane,
are consistent with an earlier conjecture based on string/5-brane duality.
