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This is a tracking category for CS1 citations that have |zbl= errors.

Help desk

Check |zbl= value

When Citation Style 1 and Citation Style 2 templates contain |zbl=, a test is done to see if the Zbl identifier value looks like a properly defined value. The |zbl= identifier is checked to make sure that it has the form: nnnn.nnnnn where n is any digit 0–9. Up to three leading zeros in the first quartet may be omitted. Further validation of the Zbl identifier is not performed.

To resolve this error, ensure that the |zbl= value is correct.

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