Software error:

Invalid data, cannot decode metadata object (biblio_metadata.id=28793, biblionumber=26830, format=marcxml, schema=MARC21, decoding_error=':19: parser error : PCDATA invalid Char value 27
    <subfield code="a">3540614559 (pbk. : acidb-sfree paper)</subfield>
                                              ^
:19: parser error : PCDATA invalid Char value 27
    <subfield code="a">3540614559 (pbk. : acidb-sfree paper)</subfield>
                                                 ^')

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