摘要 : This paper presents the first purely algebraic characterization of classes ofpartial algebras definable by a set of strong equations. This result was posible due to newtools such as invariant congruences, i.e. a generalization of ... 展开 This paper presents the first purely algebraic characterization of classes ofpartial algebras definable by a set of strong equations. This result was posible due to newtools such as invariant congruences, i.e. a generalization of the notion of a fully invariantcongruence, and extension of algebras, specific for strong equations. 收起