issue 2 publication date 2015-11-01

• Characterization and axiomatization of all semigroups whose square is group
• When does the complement of the annihilating-ideal graph of a commutative ring admit a cut vertex?
• Ultra and Involution Ideals in $BCK$-algebras
• The structure of a pair of nilpotent Lie algebras
• On the nil-clean matrix over a UFD
• $z^circ$-filters and related ideals in $C(X)$