A waiver or partial waiver of author fees (max 20%) may be decided by the editor in case of lack of funding, excessive length of submitted manuscript or other sound reasons provided by the author during the submission. The author should clearly declare that he asks for a waiver in the comments to the Editor box during their submission. The waiver will have no effect on the review result of the paper. A waiver is most likely to be denied if it is not asked in this stage.