1. Relativity and Modern Physics;Birkhoff,1923
2. On the general spherically symmetric solutions of Einstein's gravitational equations in vacuo;Jebsen;Gen. Relativ. Gravit.,2005
3. Event horizons in static vacuum space-times;Isreal;Phys. Rev.,1967
4. Exact Solutions of Einstein's Field Equations;Stephani,2003
5. Gravitational field of a spinning mass as an example of algebraically special metrics;Kerr;Phys. Rev. Lett.,1963