Upper and Lower \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-Continuity

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DOI: https://doi.org/10.28924/2291-8639-24-2026-346
Published: Oct 15, 2026
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Prapart Pue-on, Chiranya Rerkpiboon, Chawalit Boonpok, Upper and Lower \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-Continuity, Int. J. Anal. Appl., 24 (2026), 346.

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Prapart Pue-on, Chiranya Rerkpiboon, Chawalit Boonpok

Abstract

This paper presents new concepts of continuous multifunctions defined between an ideal topological space and a bitopological space, namely upper \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-continuous multifunctions and lower \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-continuous multifunctions. Furthermore, several characterizations and some properties concerning upper \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-continuous multifunctions and lower \(s\)-\(\tau^\star(\sigma_1,\sigma_2)\)-continuous multifunctions are discussed.

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