@article{Barmpalias2011KolmogorovComplexityInitial,
  year      = 2011,
  publisher = {Elsevier},
  volume    = {412},
  number    = {41},
  pages     = {5656--5667},
  author    = {G. Barmpalias and C. S. Vlek},
  title     = {Kolmogorov complexity of initial segments of sequences and arithmetical definability},
  journal   = {Theor. Comput. Sci.},
}