Isolated horizons in classical and quantum gravity
  Isolated horizons are a quasi-local framework, developed over the last 15 years by many authors, for modeling black holes `in equilibrium' that involves assumptions only about geometric structures intrinsic to the horizon. We review the motivations for the framework, and the derivation of the key results, both classical and quantum. 
Jonathan Engle and Tomas Liko
gr-qc hep-th