https://support.nature.com/en/support/solutions/articles/6000281970-access-restricted-error-when-requesting-an-article-processing-charge-discount
Access restricted error when requesting an article processing charge discount : Nature Support
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https://support.nature.com/en/support/solutions/articles/6000257466-apc-article-processing-charge-important-notes
APC Article Processing Charge Important Notes : Nature Support
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