Uniqueness of stationary, electro-vacuum black holes revisited
  In recent years there has been some progress in the understanding of the global structure of stationary black hole space-times. In this paper we review some new results concerning the structure of stationary black hole space-times. In particular we prove a corrected version of the ``black hole rigidity theorem'', and we prove a uniqueness theorem for static black holes with degenerate connected horizons. This paper is an expanded version of a lecture given at the Journ\'ees relativistes in Ascona, May 1996. 
Piotr T. Chru\'sciel