ON SOME o-SCHUNCK CLASSES

Abstract

In this paper,Ore's generalized theorems given in [4] are used to study some special o-Schunck classes. Thus we prove that: 1) the equivalence of D, A and B properties (given in [7] and [3]) on a o-Schunck class takes place; 2) the "composite" of two o-Schunck classes with the D property is in turn a o-Schunck class with the D property; 3) the class D of all o-Schunck classes with the D property, ordered by inclusion, forms respect to the operations of "composite" and intersection a complete lattice.