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error: Uncaught Error: Call to a member function getData() on null in /var/www/html/ojs3/classes/search/ArticleSearchIndex.inc.php:38
Stack trace:
#0 /var/www/html/ojs3/plugins/importexport/esci/filter/esciXmlArticleFilter.inc.php(61): ArticleSearchIndex->submissionMetadataChanged()
#1 /var/www/html/ojs3/lib/pkp/classes/filter/Filter.inc.php(449): esciXmlArticleFilter->process()
#2 /var/www/html/ojs3/plugins/importexport/esci/esciImportExportPlugin.inc.php(313): Filter->execute()
#3 /var/www/html/ojs3/plugins/importexport/esci/esciImportExportPlugin.inc.php(148): esciImportExportPlugin->importSubmissions()
#4 /var/www/html/ojs3/lib/pkp/pages/management/PKPToolsHandler.inc.php(94): esciImportExportPlugin->display()
#5 /var/www/html/ojs3/lib/pkp/classes/core/PKPRouter.inc.php(397): PKPToolsHandler->importexpo