On the Equivalence of Brans-Dicke and Einstein Theories with Static   Black Holes
  A `no-hair' theorem for the Brans-Dicke field, in the domain of outer communications of a static black hole, is established, when the trace of the energy-momentum tensor, T, is a definite-sign scalar. This implies that Brans-Dicke theory of gravitation, for matter with T of definite sign, is equivalent to Einstein gravity with the constraint T=0. 
Eloy Ay\'on (Grupo de F\'isica Te\'orica, Centro de Matem\'aticas y   F\'isica Te\'orica, ICIMAF, Cuba)