@article{Polák_2006, title={Small conjunctive varieties of regular languages}, volume={17}, url={https://cyber.bibl.u-szeged.hu/index.php/actcybern/article/view/3699}, abstractNote={The author’s modification of Eilenberg theorem relates the so-called conjunctive varieties of regular languages with pseudovarieties of idempotent semirings. Recent results by Pastijn and his co-authors lead to the description of the lattice of all (pseudo)varieties of idempotent semirings with idempotent multiplication. We describe here the corresponding 78 varieties of languages.}, number={4}, journal={Acta Cybernetica}, author={Polák, Libor}, year={2006}, month={Jan.}, pages={825-841} }