Closure operators on the lattice of radical classes of lattice ordered groups
Ján Jakubík · Czechoslovak Mathematical Journal · 1988
The notion of radical class of lattice ordered groups was introduced in [7]; cf. also [8], [1], [9], [4], [10].In this note there will be investigated a question proposed by M. Darnel [4] concerning permutability of certain closure operators on the lattice of radical classes of lattice ordered groups.