Mi. Anokhin, A BASIS OF IDENTITIES OF A VARIETY GENERATED BY A FINITELY-BASED QUASI-VARIETY OF GROUPS, Sbornik. Mathematics, 189(7-8), 1998, pp. 1115-1124
Examples are constructed of soluble finitely-based quasi-varieties of
groups that generate non-finitely based varieties (with degree of solu
bility at most 7).