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With the introduction of Advance - the option to publish an article online before (in Advance of) including it in a regular journal issue - an article can have different two publication dates for publication online: as a separate article and as publication in an online and printed issue. For this reason two <pub-date> elements can be included in the XML, using the date-type- attribute to distinguish between the Advance online publication date and the incorporation in an issue:
- A <pub-date publication-format="online" date-type="article">-element is required:
- The date, month and year information in the element corresponds with the date of first-delivery of an XML-package that contains the article. This could either be the date of publication in Advance or a first online-publication date as part of an issue.
- Once set, a publication date with date-type="article" is never changed.
- For those journals that mention the online publication date also in the PDF, the same date is used.
- A <pub-date publication-format="online" date-type="issue">-element is required, as soon as the article is included in an issue:
- The date, month and year information in the element corresponds with the date of delivery of the issue XML-package.
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