Updates are available Erratum dated 2019-10-18

Article History

Received: 5 December 2016

Accepted: 13 July 2017

First Online: 5 August 2017

Change Date: 18 October 2019

Change Type: Erratum

Change Date: 18 October 2019

Change Type: Erratum

Change Details: In the third paragraph on p. 2421 and in Theorem 1��� of [3] it is wrongly assumed that ���the multiplication on a topological semigroup T can be extended to a right continuous multiplication on ��T���; in other words, we wrongly assume that �����T is a compact Hausdorff right-topological semigroup for any topological semigroup T���. So using [3, Theorem 1] we can only obtain the following two theorems in place of [3, Theorem 1���], where X��� denotes the limit-point set of a space X and J(E) denotes the set of all idempotents in a compact Hausdorff right-topological semigroup E.

Change Details: In the third paragraph on p. 2421 and in Theorem 1��� of [3] it is wrongly assumed that ���the multiplication on a topological semigroup T can be extended to a right continuous multiplication on ��T���; in other words, we wrongly assume that �����T is a compact Hausdorff right-topological semigroup for any topological semigroup T���. So using [3, Theorem 1] we can only obtain the following two theorems in place of [3, Theorem 1���], where X��� denotes the limit-point set of a space X and J(E) denotes the set of all idempotents in a compact Hausdorff right-topological semigroup E.