Category:CS1 errors: ISSN

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Administrators: Please do not delete this category as empty! This category may be empty occasionally or even most of the time.

This is a tracking category for CS1 citations that have ISSN errors.

Help desk

Citation Style 1 and Citation Style 2 templates that contain |issn= and/or |eissn= are checked to ensure that the ISSN is the proper length (eight digits) and that the final check digit validates according to the ISSN specification. Only one each of ISSN and eISSN is allowed in this field because the whole |issn= and |eissn= values are included in the citation's COinS metadata. See also Wikipedia:COinS. (If relevant, they can be specified using |id={{ISSN|...}} {{EISSN|...}} instead.)

The ISSN and eISSN are always rendered as two four-digit numbers separated with a hyphen.

To resolve this error, ensure that the |issn= and |eissn= values are correct, that only one value per parameter is used, and that no other text is included (allowable characters are 0–9, X, and -). If the check-digit is a lowercase 'x', change it to an uppercase 'X'. It may also be worth checking an actual hyphen (-) has been used, and not a hyphen-like character like an endash (–).

In very rare cases, publishers have released works with a malformed identifier. If you are certain that a non-conforming identifier truly corresponds to the published work, then you can add accept-this-as-written markup around the identifier to suppress the error message. In some cases, works may have been reissued with a corrected identifier. Use the corrected one when possible.

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

• Category:Pages with ISSN errors, for ISSN errors identified by {{ISSN}}
• Category:Articles with invalid ISSNs
• Category:CS1 maint: ignored ISSN errors