All articles published for full open access. In order to provide free access to readers, and to cover the costs of peer review, copyediting, typesetting, long-term archiving, and journal management, an article processing charge (APC) applies to papers accepted after peer review. In addition to US Dollar, we also accept payments like Euros (EUR), US Dollars (USD) or British Pound Sterling (GBP), Swiss Francs (CHF) etc.