Universal Quasivarieties of Algebras
نویسنده
چکیده
Two different notions of universal, one due to Hedrlín and Pultr in the 1960s and the other due to Sapir in the 1980s, are discussed, as well as the relationship between them. Some of the historical perspective and mathematical motivation lying behind them is also included, together with a brief overview of a variety meriting further investigation in this context.
منابع مشابه
OPTIMAL NATURAL DUALITIES FOR SOME QUASIVARIETIES OF DISTRIBUTIVE DOUBLE p–ALGEBRAS
Quasivarieties of distributive double p-algebras generated by an ordinal sum M of two Boolean lattices are considered. Globally minimal failsets within S(M2) are completely determined; from them all the optimal dualities for these quasivarieties are obtained.
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