Text and Data Mining valid from 2019-12-02
First Online: 2 December 2019
Compliance with Ethical Standards
: No sources of funding were used to conduct this study or prepare this manuscript.
: Pedro Renato de Paula Brandão, Simoneide S. Titze-de-Almeida, and Ricardo Titze-de-Almeida have no conflicts of interest that are directly relevant to the content of this study.