View source for Quasi-variety

See [[Algebraic systems, quasi-variety of|Algebraic systems, quasi-variety of]].

====Comments====
As noted in (the editorial comments to) [[Algebraic systems, quasi-variety of|Algebraic systems, quasi-variety of]], the quasi-identities (cf. [[Quasi-identity|Quasi-identity]]) defining a quasi-variety are usually called Horn sentences. Correspondingly, a quasi-variety is also known as a universal Horn class; it is also called a quasi-primitive class.

====References====
<table><TR><TD valign="top">[a1]</TD> <TD valign="top">  P.M. Cohn,   "Universal algebra" , Reidel  (1981)  pp. 235</TD></TR></table>