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This category encompasses articles that refer to periodicals which need their ISSN numbers added so that Wikipedians can find copies of them. Articles are added to the category by use of the template {{ISSN-needed}}. Articles are also added to this category when an ISSN is not provided in the {{Infobox Journal}} template.

To add the tag, type the following:

{{ISSN-needed}}

To find or confirm ISSNs for publications, try the following:

• Library of Congress catalog
• WorldCat advanced search

category:Articles with invalid ISSNs