Fatal error: Uncaught Error: Undefined constant "ORDERBY_DATE_PUBLISHED" in /var/www/omp/lib/pkp/pages/catalog/PKPCatalogHandler.inc.php:57
Stack trace:
#0 /var/www/omp/lib/pkp/classes/core/PKPRouter.inc.php(397): PKPCatalogHandler->category(Array, Object(Request))
#1 /var/www/omp/lib/pkp/classes/core/PKPPageRouter.inc.php(246): PKPRouter->_authorizeInitializeAndCallRequest(Array, Object(Request), Array, false)
#2 /var/www/omp/lib/pkp/classes/core/Dispatcher.inc.php(144): PKPPageRouter->route(Object(Request))
#3 /var/www/omp/lib/pkp/classes/core/PKPApplication.inc.php(362): Dispatcher->dispatch(Object(Request))
#4 /var/www/omp/index.php(65): PKPApplication->execute()
#5 {main}
thrown in /var/www/omp/lib/pkp/pages/catalog/PKPCatalogHandler.inc.php on line 57