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This category contains pages that contains invalid digital object identifiers (DOIs). It is populated by {{doi}}. To clean up, ensure that the DOI is specified as:
{{doi|10.Foobar/1234}}and not{{doi|doi:10.Foobar/1234}}{{doi|10.Foobar/1234}}and not{{doi|http://dx.doi.org/10.Foobar/1234}}
or similar. DOI values are marked as invalid if they do not begin with 10.