@article{HoffmanKlarner1979,
  author    = {{Dean G. Hoffman and David A. Klarner}},
  title     = {{Sets of integers closed under affine operators- the finite basis theorems}},
  journal   = {{Pacific Journal of Mathematics}},
  year      = {{1979}},
  volume    = {{83}},
  number    = {{1}},
  pages     = {{135--144}},
  note      = {{MR 83e:10080}},
}