"Gravitation and Spacetime", W.W. Norton (1994); translated into Italian (Bologna: Zanichelli, 1997) and Korean (Seoul: Shin Won, 2001)*Bardeen, et al., "Black Holes", Gordon & Breach (1973)*M. Rees, J.A.
"Gravitation and Spacetime", W.W. Norton, N.Y. (1994) also Translated into Italian (Zanichelli, Bologna, 1997) and Korean (Shin Won, Seoul, 2001).