Congruence restrictions on axes Jaromír Duda (1992) Mathematica Bohemica Similarity: We give Mal’cev conditions for varieties 4V4 whose congruences on the product A × B , A , B ∈ V , are determined by their restrictions on the axes in A × B .
On the degrees of permutability of subregular varieties Graham D. Barbour, James G. Raftery (1997) Czechoslovak Mathematical Journal Similarity:
The Csákány theory of regularity for finite algebras Ivan Chajda (1995) Mathematica Slovaca Similarity: