Authors from developing or less developed countries should see the Journal Processing Charges page for possible discount / reduction in APC for the current issue, due for publication this month. However, a nominal Article Processing Charge (APC) of 25 USD is charged for processing each accepted manuscript.
The article processing charge covers the range of publishing services such as:
i. costs of administrating the peer review system and editorial coordination,
ii. manuscript editing for publication,
iii. journal production (i.e. layout and formatting),
iv. open access online publication and hosting,
v. CrossRef DOI annual fee,
vi. CrossRef DOI article deposits fee,
vii. indexing and achieving fees,
viii. online content/journal promotion fees