Geodesic
On the congruences of the direct product of algebra
Algebra i logika, Tome 6 (1967) no. 1, pp. 39-43.

Voir la notice de l'article provenant de la source Math-Net.Ru

An example is given of the direct product $\mathscr{O}\times\mathscr{L}$ of two simple algebras $\mathscr{O}$, $\mathscr{L}$ (of $2$ and $3$ order), where the lattice of congruences is modular and the congruences are not permutable. 
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     author = {A. F. Bravcev},
     title = {On the congruences of the direct product of algebra},
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A. F. Bravcev. On the congruences of the direct product of algebra. Algebra i logika, Tome 6 (1967) no. 1, pp. 39-43. http://geodesic.mathdoc.fr/item/AL_1967_6_1_a4/