(Sub)fit biframes and non-symmetric nearness

@article{Picado2014SubfitBA,
  title={(Sub)fit biframes and non-symmetric nearness},
  author={J. Picado and A. Pultr},
  journal={Topology and its Applications},
  year={2014},
  volume={168},
  pages={66-81}
}
Abstract The non-symmetric (quasi-)nearness and its generalized admissibility are studied both in its biframe and paircovers aspect and in the perspective of entourages. The necessary and sufficient condition for a biframe to carry such an enrichment is shown to be a biframe variant of subfitness (resp. fitness, in the hereditary case). 
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