ACTA issues

## Dual discriminator, revisited

Ervin Fried

Acta Sci. Math. (Szeged) 64:3-4(1998), 437-453
3298/2009

 Abstract. The first part of the paper simplifies proofs of some basic theorems of the original paper [4]. The second part presents a general method for constructing dual discriminator varieties with \$2^{\aleph_0}\$ subvarieties, in contrast to the complicated single variety given in [1]. AMS Subject Classification (1991): 08B10, 08A30 Keyword(s): Varieties, filtrality, dual discriminators, definable principal congruences Received August 15, 1995 and in revised form June 22, 1998. (Registered under 3298/2009.)