TY  - JOUR
T1  - Dominions and closed varieties of bands
AU  - Ashraf, Wajih
AU  - Abbas, Shabnam
AU  - Khan, Noor Mohammad
PY  - 2024
DA  - April
DO  - 10.15672/hujms.1217130
JF  - Hacettepe Journal of Mathematics and Statistics
PB  - Hacettepe University
WT  - DergiPark
SN  - 2651-477X
SP  - 382
EP  - 391
VL  - 53
IS  - 2
LA  - en
AB  - We show that all subvarieties of the variety of rectangular bands are closed in the variety of $n$-nilpotent extension of bands. Ahanger, Nabi and Shah in [1] have proved that the variety of regular bands is closed. In this paper, we improve this result and provide its simple and shorter proof. Finally, we show that all subvarieties of the variety of normal bands are closed in the variety of left [right] semiregular bands.
KW  - identity
KW  - varieties
KW  - zigzag equations
KW  - dominion
KW  - bands
KW  - rectangular
KW  - normal
KW  - regular
KW  - left semiregular
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UR  - https://doi.org/10.15672/hujms.1217130
L1  - https://dergipark.org.tr/en/download/article-file/2823544
ER  -