Sets Which Do Not Have Subsets of Every Higher Degree

Stephen G. Simpson. Sets Which Do Not Have Subsets of Every Higher Degree. Journal of Symbolic Logic, 43(1):135-138, 1978.

@article{Simpson78,
  title = {Sets Which Do Not Have Subsets of Every Higher Degree},
  author = {Stephen G. Simpson},
  year = {1978},
  researchr = {https://researchr.org/publication/Simpson78},
  cites = {0},
  citedby = {0},
  journal = {Journal of Symbolic Logic},
  volume = {43},
  number = {1},
  pages = {135-138},
}