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

Help desk

Check |hdl= value

When Citation Style 1 and Citation Style 2 templates contain |hdl=, a test is done to see if the hdl value looks like a properly defined value. The |hdl= value is checked to make sure that it does not contain spaces or en dashes and does not end with punctuation. Further validation of the hdl is not performed.

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

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