Open Access Policy

PER is an open access journal which means that all content is freely available without charge to the user or his/her institution. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles in this journal without asking prior permission from the publisher or the author. This is in accordance with the BOAI definition of open access.

Creative Commons Licenses

All published articles in PER are published under Creative Commons Attribution License (CC-BY 4.0). Any further distribution or use of content published under CC BY 4.0 must contain the author(s) and the published article’s title, journal citation, and DOI .All articlespublished in PER under a CC BY License may be used for Text and Data Mining purposes, subject to the conditions of the CC BY License terms.