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A factorization of elements in PSL(2, F), where F = Q, R
Hyperidentities in associative graph algebras
The order of normalform hypersubstitutions of type (2)
Some classes of Diophantine equations connected with McFarland's and Ma's conjectures
Diophantine equations and class number of imaginary quadratic fields
Relatively complemented ordered sets
Congruences on pseudocomplemented semilattices
Localization in semicommutative (m,n)-rings
Linear operators preserving maximal column ranks of nonbinary boolean matrices