On an aspect of scatteredness in the point-free setting

@article{Ball2016OnAA,
  title={On an aspect of scatteredness in the point-free setting},
  author={R. Ball and J. Picado and A. Pultr},
  journal={Portugaliae Mathematica},
  year={2016},
  volume={73},
  pages={139-152}
}
It is well known that a locale is subfit iff each of its open sublocales is a join of closed ones, and fit iff each of its closed sublocales is a meet of open ones. This formulation, however, exaggerates the parallelism between the behavior of fitness and subfitness. For it can be shown that a locale is fit iff each of its sublocales is a meet of closed ones, but it is not the case that a locale is subfit iff each of its sublocales is a join of closed ones. Thus we are led to take up the very… Expand
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