Text and Data Mining valid from 2018-05-18
Received: 9 January 2018
Accepted: 2 May 2018
First Online: 18 May 2018
Change Date: 3 July 2018
Change Type: Correction
Change Details: A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
: The authors declare no competing interests.