UPPER AND LOWER NA-CONTINUOUS MULTIFUNCTIONS

The aim of this paper is to introduce a new class of continuous multifunctions, namely upper and lower na-continuous multifunctions, and to obtain some characterizations concerning upper and lower nacontinuous multifunctions. The authors investigate the graph of upper and lower na-continuous multifunctions, and the preservation of properties under upper na-continuous multifunctions. Also, the relationship between upper and lower na-continuous multifunctions and some known types of continuous multifunctions are discussed.

Keywords:

α-open sets, δ-open sets, multifunctions, α-compact spaces, δ-connected spaces 2010 AMS Classification: 54 C 60,

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