On chromatic number of graphs and set-systems

  title={On chromatic number of graphs and set-systems},
  author={Paul L. Erdos and Andr{\'a}s Hajnal},
  journal={Acta Mathematica Academiae Scientiarum Hungarica},
  • P. Erdos, A. Hajnal
  • Published 1 March 1966
  • Mathematics
  • Acta Mathematica Academiae Scientiarum Hungarica
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