@article{Gimbutas2007,
  author    = {Marija Gimbutas},
  title     = {The beginning of the bronze age in Europe and the indo-europeans : 3500-2500 B.C.},
  journal   = {The journal of Indo-European studies},
  volume    = {1},
  pages     = {163 -- 214},
  year      = {2007},
}