Fatal error: Uncaught Error: Call to a member function getDisplayName() on null in /var/www/html/ojs/lib/pkp/classes/galley/Galley.php:160 Stack trace: #0 /var/www/html/ojs/cache/t_compile/e35ba3ad88c8e24bc4de57abe8230f54bf65149d^9190456890661656c2db668fc3c363ee4354c517_0.app.frontendobjectsgalley_link.tpl.php(73): PKP\galley\Galley->getGalleyLabel() #1 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_6871494e3c5002_88299316() #2 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode() #3 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(384): Smarty_Template_Compiled->render() #4 /var/www/html/ojs/cache/t_compile/e35ba3ad88c8e24bc4de57abe8230f54bf65149d^7cf1cd52b8ba8108de77f197078de34b733dd394_0.app.frontendobjectsarticle_summary.tpl.php(106): Smarty_Internal_Template->_subTemplateRender() #5 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_6871494e45a8b9_69307275() #6 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode() #7 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(384): Smarty_Template_Compiled->render() #8 /var/www/html/ojs/cache/t_compile/e35ba3ad88c8e24bc4de57abe8230f54bf65149d^26de9c47ced54328a8eb56e39bb4d4079aa049c6_0.app.frontendobjectsissue_toc.tpl.php(158): Smarty_Internal_Template->_subTemplateRender() #9 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_6871494e3abd69_38305886() #10 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode() #11 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(217): Smarty_Template_Compiled->render() #12 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(386): Smarty_Internal_Template->render() #13 /var/www/html/ojs/cache/t_compile/e35ba3ad88c8e24bc4de57abe8230f54bf65149d^fcbc2cabc0d4dff6219d7e4b5d36c1363533cfd8_0.app.frontendpagesissue.tpl.php(43): Smarty_Internal_Template->_subTemplateRender() #14 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_6871494e3028a2_38019416() #15 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode() #16 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(217): Smarty_Template_Compiled->render() #17 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(238): Smarty_Internal_Template->render() #18 /var/www/html/ojs/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(134): Smarty_Internal_TemplateBase->_execute() #19 /var/www/html/ojs/lib/pkp/classes/template/PKPTemplateManager.php(1369): Smarty_Internal_TemplateBase->display() #20 /var/www/html/ojs/pages/issue/IssueHandler.php(138): PKP\template\PKPTemplateManager->display() #21 [internal function]: APP\pages\issue\IssueHandler->view() #22 /var/www/html/ojs/lib/pkp/classes/core/PKPRouter.php(334): call_user_func() #23 /var/www/html/ojs/lib/pkp/classes/core/PKPPageRouter.php(278): PKP\core\PKPRouter->_authorizeInitializeAndCallRequest() #24 /var/www/html/ojs/lib/pkp/classes/core/Dispatcher.php(165): PKP\core\PKPPageRouter->route() #25 /var/www/html/ojs/lib/pkp/classes/core/PKPApplication.php(395): PKP\core\Dispatcher->dispatch() #26 /var/www/html/ojs/index.php(21): PKP\core\PKPApplication->execute() #27 {main} thrown in /var/www/html/ojs/lib/pkp/classes/galley/Galley.php on line 160