Using a construction theorem of cryptogroups and congruence methods, we determine an 18-element lattice, generated by {NOBG, ROBG, OBG, NBA, RBA, BA}, of subvarieties of completely regular semigroups.
基金supported by the National Natural Science Foundation of China (Grant No. 10871161)the Research Foundations for Doctor Programme of Southwest University (Grant Nos. SWNUB2005020,SWNUB2008001)
文摘Using a construction theorem of cryptogroups and congruence methods, we determine an 18-element lattice, generated by {NOBG, ROBG, OBG, NBA, RBA, BA}, of subvarieties of completely regular semigroups.
