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A characterization of cubic subalgebra is established. The notion of internal and external cubic subalgebra in BCK/BCI-algebra and several properties are investigated. The R-union, R-intersection, P-union, and P-intersection of internal and external cubic subalgebras in BCK/BCI-algebra are discussed.


Cubic subalgebra internal cubic subalgebra external cubic subalgebra.

Article Details

How to Cite
Bordbar, H., Zahedi, M. M., & Jun, Y. B. (2021). Internal and External Cubic Subalgebras of BCK/BCI-Algebras. Journal of the Indonesian Mathematical Society, 27(1), 48–63.


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