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