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Insertion of Continuous Real Functions on Spaces, Bispaces, Ordered Spaces and Pointfree Spaces—A Common Root

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Abstract

We characterize normal and extremally disconnected biframes in terms of the insertion of a continuous real function in between given lower and upper semicontinuous real functions and show this to be the common root of several classical and new insertion results concerning topological spaces, bitopological spaces, ordered topological spaces and locales.

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Authors and Affiliations

  1. CMUC, Department of Mathematics, University of Coimbra, 3001-454, Coimbra, Portugal

    Maria João Ferreira & Jorge Picado

  2. Departamento de Matemáticas-Matematika Saila, Universidad del País Vasco-Euskal Herriko Unibertsitatea, Apartado, 644, Bilbao, Spain

    Javier Gutiérrez García

Authors
  1. Maria João Ferreira
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  2. Javier Gutiérrez García
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  3. Jorge Picado
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Correspondence to Jorge Picado.

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Ferreira, M.J., Gutiérrez García, J. & Picado, J. Insertion of Continuous Real Functions on Spaces, Bispaces, Ordered Spaces and Pointfree Spaces—A Common Root. Appl Categor Struct 19, 469–487 (2011). https://doi.org/10.1007/s10485-009-9209-0

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  • DOI: https://doi.org/10.1007/s10485-009-9209-0

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