Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{MASLO_1989__39_4_a2, author = {Duda, Jarom{\'\i}r}, title = {Principal congruence relations and principal tolerances on varieties of lattices}, journal = {Mathematica slovaca}, pages = {365--369}, publisher = {mathdoc}, volume = {39}, number = {4}, year = {1989}, mrnumber = {1094759}, zbl = {0753.06005}, language = {en}, url = {http://geodesic.mathdoc.fr/item/MASLO_1989__39_4_a2/} }
Duda, Jaromír. Principal congruence relations and principal tolerances on varieties of lattices. Mathematica slovaca, Tome 39 (1989) no. 4, pp. 365-369. http://geodesic.mathdoc.fr/item/MASLO_1989__39_4_a2/