Text and Data Mining valid from 2018-10-18
Received: 19 February 2018
Accepted: 4 October 2018
First Online: 18 October 2018
Change Date: 28 May 2019
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 been fixed in the paper.
: The authors declare no competing interests.