Rg is an open access journal, which means that all content is freely available without charge to the user or his/her institution. Users may read, download, copy, distribute, print, search, and link to the full-text articles as well as use them for any lawful purpose without obtaining prior permission from the publisher or author.
Starting with volume 27 (2019), all new journal content is published under a Creative Commons CC BY International 4.0 license. This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. The license allows for commercial use.
All former volumes continue to apply to the previously used license (Creative Commons BY-NC-ND 3.0 DE: Attribution-NonCommercial-NoDerivatives). This license allows reusers to copy and distribute the material in any medium or format in unadapted form only, for noncommercial purposes only, and only so long as attribution is given to the creator.
For more information on Creative Commons licenses, please visit: https://creativecommons.org/about/cclicenses/
Each author publishing in Rg holds the copyright and retains the publishing rights of his/her article without restriction.