@article{Schmidt2013,
  author    = {Hans-J{\"u}rgen Schmidt},
  title     = {The tetralogy of Birkhoff theorems},
  journal   = {General relativity and gravitation},
  volume    = {45},
  number    = {2},
  pages     = {395 -- 410},
  doi       = {10.1007/s10714-012-1478-5},
  year      = {2013},
}