Text and Data Mining valid from 2019-11-21
First Online: 21 November 2019
Compliance with Ethical Standards
: No funding has been received for the conduct of this analysis or the preparation of this article.
: Dmitry Y. Litvinov, Eugeny V. Savushkin and Alexander D. Dergunov have no conflicts of interest that are directly relevant to the content of this article.
: This article does not contain any studies with human participants or animals performed by any of the authors.