MathSciDoc: An Archive for Mathematician ∫

@inproceedings{leif1961on,
  title={On the cohomology of two-stage Postnikov systems},
  author={Leif Kristensen},
  url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203158475457933},
  booktitle={Acta Mathematica},
  volume={107},
  number={1},
  pages={73-123},
  year={1961},
}