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It is used to build and maintain a list or lists of pages—primarily for the sake of the lists themselves and their use in article and category maintenance. It is not part of the encyclopedia's categorization scheme.

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This is a tracking category for {{cite arXiv}} templates that use |class= improperly.

Help desk

|class= ignored

Only used in {{cite arXiv}} templates, |class= is only appropriate when the template uses |arxiv=YYMM.NNNN or |arxiv=YYMM.NNNNN identifier formats; see Cite arXiv §Usage.

To resolve this error, remove |class=.

Pages with this error are automatically placed in Category:CS1 errors: class.^[a]