diff --git a/CitationStyleLanguagePlugin.inc.php b/CitationStyleLanguagePlugin.php
similarity index 88%
rename from CitationStyleLanguagePlugin.inc.php
rename to CitationStyleLanguagePlugin.php
index 59b0c57..13bb53d 100644
--- a/CitationStyleLanguagePlugin.inc.php
+++ b/CitationStyleLanguagePlugin.php
@@ -1,7 +1,7 @@
 <?php
 
 /**
- * @file plugins/generic/citationStyleLanguage/CitationStyleLanguagePlugin.inc.php
+ * @file plugins/generic/citationStyleLanguage/CitationStyleLanguagePlugin.php
  *
  * Copyright (c) 2017-2020 Simon Fraser University
  * Copyright (c) 2017-2020 John Willinsky
@@ -13,28 +13,48 @@
  * @brief Citation Style Language plugin class.
  */
 
-use APP\facades\Repo;
-use PKP\facades\Locale;
-use PKP\plugins\GenericPlugin;
-use PKP\linkAction\request\AjaxModal;
-use PKP\linkAction\LinkAction;
-use PKP\core\JSONMessage;
-use PKP\template\PKPTemplateManager;
+namespace APP\plugins\generic\citationStyleLanguage;
 
 require_once(__DIR__ . '/lib/vendor/autoload.php');
 
+use APP\author\Author;
+use APP\core\Application;
+use APP\core\Request;
+use APP\facades\Repo;
+use APP\issue\Issue;
+use APP\monograph\Chapter;
+use APP\plugins\generic\citationStyleLanguage\pages\CitationStyleLanguageHandler;
+use APP\press\SeriesDAO;
+use APP\publication\Publication;
+use APP\publicationFormat\PublicationFormat;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Exception;
+use PKP\config\Config;
+use PKP\core\JSONMessage;
+use PKP\core\PKPApplication;
+use PKP\core\PKPRequest;
+use PKP\db\DAORegistry;
+use PKP\facades\Locale;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\plugins\GenericPlugin;
+use PKP\plugins\Hook;
+use PKP\submission\SubmissionKeywordDAO;
+use PKP\submission\SubmissionLanguageDAO;
 use Seboettg\CiteProc\CiteProc;
+use stdClass;
 
 class CitationStyleLanguagePlugin extends GenericPlugin
 {
     /** @var array List of citation styles available */
-    public $_citationStyles = [];
+    public array $_citationStyles = [];
 
     /** @var array List of citation download formats available */
-    public $_citationDownloads = [];
+    public array $_citationDownloads = [];
 
-    /** @var bool $applicationOmp */
-    private bool $applicationOmp;
+    /** @var string Name of the application */
+    public string $application;
 
     private bool $book = false;
     private bool $chapter = false;
@@ -45,8 +65,7 @@ class CitationStyleLanguagePlugin extends GenericPlugin
      */
     public function __construct() {
         parent::__construct();
-        $applicationName = Application::get()->getName();
-        $this->applicationOmp =  stripos($applicationName, 'omp') !== false;
+        $this->application = Application::get()->getName();
     }
 
     /**
@@ -77,9 +96,12 @@ public function register($category, $path, $mainContextId = null)
             return $success;
         }
         if ($success && $this->getEnabled($mainContextId)) {
-            HookRegistry::register('CatalogBookHandler::book', [$this, 'getTemplateData']);
-            HookRegistry::register('ArticleHandler::view', [$this, 'getTemplateData']);
-            HookRegistry::register('LoadHandler', [$this, 'setPageHandler']);
+            Hook::add('CatalogBookHandler::book', [$this, 'getTemplateData']);
+            Hook::add('ArticleHandler::view', [$this, 'getTemplateData']);
+            Hook::add('Templates::Article::Details', [$this, 'addCitationMarkup']);
+            Hook::add('Templates::Catalog::Book::Details', [$this, 'addCitationMarkup']);
+            Hook::add('Templates::Catalog::Chapter::Details', [$this, 'addCitationMarkup']);
+            Hook::add('LoadHandler', [$this, 'setPageHandler']);
         }
         return $success;
     }
@@ -151,7 +173,7 @@ public function getCitationStyles()
 
         // If hooking in to add a custom .csl file, add a `useCsl` key to your
         // style definition with the path to the file.
-        HookRegistry::call('CitationStyleLanguage::citationStyleDefaults', [&$defaults, $this]);
+        Hook::call('CitationStyleLanguage::citationStyleDefaults', [&$defaults, $this]);
         $this->_citationStyles = $defaults;
 
         return $this->_citationStyles;
@@ -234,7 +256,7 @@ public function getCitationDownloads()
 
         // If hooking in to add a custom .csl file, add a `useCsl` key to your
         // style definition with the path to the file.
-        HookRegistry::call('CitationStyleLanguage::citationDownloadDefaults', [&$defaults, $this]);
+        Hook::call('CitationStyleLanguage::citationDownloadDefaults', [&$defaults, $this]);
         $this->_citationDownloads = $defaults;
 
         return $this->_citationDownloads;
@@ -296,41 +318,34 @@ public function getCitationStyleConfig($styleId)
      * Retrieve citation information for the article details template. This
      * method is hooked in before a template displays.
      *
-     * @see ArticleHandler::view()
-     *
      * @param $args array
      *
      * @return false
+     * @throws Exception
+     * @see ArticleHandler::view()
      */
     public function getTemplateData($hookName, $args)
     {
-        $templateMgr = TemplateManager::getManager();
         $request = $args[0];
-        if ($this->isApplicationOmp()) {
-            $submission =& $args[1];
-            $publication = $request->_router->_handler->publication;
-            if ( $request->_router->_handler->isChapterRequest ) {
-                $chapter = $request->_router->_handler->chapter;
-            } else {
-                $chapter = null;
-            }
+        $templateMgr = TemplateManager::getManager($request);
 
-            $issue = null;
-            $templateMgr->addStyleSheet(
-                'cslPluginStyles',
-                $request->getBaseUrl() . '/' . $this->getPluginPath() . '/css/citationStyleLanguagePlugin.css',
-                [
-                    'priority' => PKPTemplateManager::STYLE_SEQUENCE_LAST,
-                    'contexts' => ['frontend'],
-                    'inline'   => false,
-                ]
-            );
-        } else {
-            $issue = $args[1];
-            $submission = $args[2];
-            $publication = $args[3];
-            $chapter = null;
+        switch ($this->application) {
+            case 'ojs2':
+                $issue = $args[1];
+                $submission = $args[2];
+                $publication = $args[3];
+                $chapter = null;
+                break;
+            case 'omp':
+                /** @var Submission $submission */
+                $submission =& $args[1];
+                $publication =& $args[2];
+                $chapter =& $args[3];
+                $issue = null;
+                break;
+            default: throw new Exception('Unknown application!');
         }
+
         $context = $request->getContext();
         $contextId = $context ? $context->getId() : 0;
 
@@ -352,6 +367,16 @@ public function getTemplateData($hookName, $args)
             'citationDownloads' => $this->getEnabledCitationDownloads($contextId),
         ]);
 
+        $templateMgr->addStyleSheet(
+            'cslPluginStyles',
+            $request->getBaseUrl() . '/' . $this->getPluginPath() . '/css/citationStyleLanguagePlugin.css',
+            [
+                'priority' => TemplateManager::STYLE_SEQUENCE_LAST,
+                'contexts' => ['frontend'],
+                'inline'   => false,
+            ]
+        );
+
         $templateMgr->addJavaScript(
             'citationStyleLanguage',
             $request->getBaseUrl() . '/' . $this->getPluginPath() . '/js/articleCitation.js'
@@ -360,20 +385,9 @@ public function getTemplateData($hookName, $args)
         return false;
     }
 
-    /**
-     * Add citation style language to book view page
-     * Hooked to `Templates::Catalog::Book::Main`
-     *
-     * @param $hookName string
-     * @param $params   array array [
-     * @option Smarty
-     * @option string HTML output to return
-     * ]
-     * @return false
-     */
-    public function displayCitationMonograph($hookName, $params) {
-        $smarty =& $params[1];
-        $output =& $params[2];
+    public function addCitationMarkup($hookName, $args) {
+        $smarty =& $args[1];
+        $output =& $args[2];
         $output .= $smarty->fetch($this->getTemplateResource('citationblock.tpl'));
 
         return false;
@@ -389,21 +403,22 @@ public function displayCitationMonograph($hookName, $params) {
      * @see Zotero's mappings https://aurimasv.github.io/z2csl/typeMap.xml#map-journalArticle
      * @see Mendeley's mappings http://support.mendeley.com/customer/portal/articles/364144-csl-type-mapping
      *
-     * @param $request PkPRequest
-     * @param $submission Submission
+     * @param $request       PkPRequest
+     * @param $submission    Submission
      * @param $citationStyle string Name of the citation style to use.
-     * @param $issue Issue Optional. Will fetch from db if not passed.
-     * @param $publication Publication Optional. A particular version
-     * @param $chapter Chapter Optional. OMP chapter pages only.
+     * @param $issue         Issue Optional. Will fetch from db if not passed.
+     * @param $publication   Publication Optional. A particular version
+     * @param $chapter       Chapter Optional. OMP chapter pages only.
      *
      * @return string
+     * @throws Exception
      */
     public function getCitation($request, $submission, $citationStyle = 'apa', $issue = null, $publication = null, $chapter = null)
     {
         $publication = $publication ?? $submission->getCurrentPublication();
         $context = $request->getContext();
         if (!$chapter) {
-            $chapter = $this->isApplicationOmp() ? $this->getChapter($request, $publication) : null;
+            $chapter = $this->application === 'omp' ? $this->getChapter($request, $publication) : null;
         }
         $this->setDocumentType($chapter);
         /* @var $submissionKeywordDao SubmissionKeywordDAO */
@@ -510,12 +525,12 @@ public function getCitation($request, $submission, $citationStyle = 'apa', $issu
                     $citationData->{'original-date'}->raw = htmlspecialchars($originalPublication->getData('datePublished'));
                 }
             }
-        } elseif (!$this->isApplicationOmp() && $issue && $issue->getPublished()) {
+        } elseif ($this->application === 'ojs2' && $issue && $issue->getPublished()) {
             $citationData->issued = new stdClass();
             $citationData->issued->raw = htmlspecialchars($issue->getDatePublished());
         }
 
-        HookRegistry::call('CitationStyleLanguage::citation', [&$citationData, &$citationStyle, $submission, $issue, $context, $publication]);
+        Hook::call('CitationStyleLanguage::citation', [&$citationData, &$citationStyle, $submission, $issue, $context, $publication]);
 
         $citation = '';
 
@@ -530,18 +545,23 @@ public function getCitation($request, $submission, $citationStyle = 'apa', $issu
                     'citationStyle' => $citationStyle,
                     'publication' => $publication,
                 ]);
-                if ($this->isApplicationOmp()) {
-                    $templateMgr->assign([
-                        'book' => $submission,
-                        'press' => $context,
-                    ]);
-                } else {
-                    $templateMgr->assign([
-                       'article' => $submission,
-                       'issue' => $issue,
-                       'journal' => $context,
-                   ]);
+                switch ($this->application) {
+                    case 'ojs2':
+                        $templateMgr->assign([
+                            'article' => $submission,
+                            'issue' => $issue,
+                            'journal' => $context,
+                        ]);
+                        break;
+                    case 'omp':
+                        $templateMgr->assign([
+                            'book' => $submission,
+                            'press' => $context,
+                        ]);
+                        break;
+                    default: throw new Exception('Unknown application!');
                 }
+
                 $citation = $templateMgr->fetch($styleConfig['useTemplate']);
             } else {
                 $style = $this->loadStyle($styleConfig);
@@ -616,10 +636,8 @@ public function loadStyle($styleConfig)
      */
     public function downloadCitation($request, $submission, $citationStyle = 'ris', $issue = null, $publication = null, $chapter = null)
     {
-        if (!$this->isApplicationOmp()) {
-            if (empty($issue)) {
-                $issue = Repo::issue()->get($submission->getCurrentPublication()->getData('issueId'));
-            }
+        if (($this->application === 'ojs2') && empty($issue)) {
+            $issue = Repo::issue()->get($submission->getCurrentPublication()->getData('issueId'));
         }
 
         $styleConfig = $this->getCitationStyleConfig($citationStyle);
@@ -691,7 +709,6 @@ public function manage($args, $request)
     {
         switch ($request->getUserVar('verb')) {
             case 'settings':
-                $this->import('CitationStyleLanguageSettingsForm');
                 $form = new CitationStyleLanguageSettingsForm($this);
 
                 if ($request->getUserVar('save')) {
@@ -718,20 +735,15 @@ public function manage($args, $request)
      */
     public function setPageHandler($hookName, $params)
     {
-        $page = $params[0];
+        $page =& $params[0];
+        $handler =& $params[3];
         if ($this->getEnabled() && $page === 'citationstylelanguage') {
-            $this->import('pages/CitationStyleLanguageHandler');
-            define('HANDLER_CLASS', 'CitationStyleLanguageHandler');
+            $handler = new CitationStyleLanguageHandler($this);
             return true;
         }
         return false;
     }
 
-    public function isApplicationOmp(): bool
-    {
-        return $this->applicationOmp;
-    }
-
     public function getEditorGroups(int $contextId = 0): array
     {
         return $this->getSetting($contextId, 'groupEditor') ?? [];
@@ -828,17 +840,23 @@ protected function getChapter(PKPRequest $request, Publication $publication): ?C
         return null;
     }
 
+    /**
+     * @throws Exception
+     */
     protected function setDocumentType($chapter): void
     {
-        if ($this->isApplicationOmp()) {
-            if ($chapter) {
-                $this->chapter = true;
-            } else {
-                $this->book = true;
-            }
-
-        } else {
-            $this->article = true;
+        switch ($this->application) {
+            case 'ojs2':
+                $this->article = true;
+                break;
+            case 'omp':
+                if ($chapter) {
+                    $this->chapter = true;
+                } else {
+                    $this->book = true;
+                }
+                break;
+            default: throw new Exception('Unknown application!');
         }
     }
 
@@ -863,7 +881,7 @@ protected function setArticleAuthors($citationData, $publication, $context): std
         $authorsGroups = $this->getAuthorGroups($context->getId());
         $translatorsGroups = $this->getTranslatorGroups($context->getId());
         if (count($authors)) {
-            /** @var \APP\author\Author $author */
+            /** @var Author $author */
             foreach ($authors as $author) {
                 $currentAuthor = new stdClass();
                 if (empty($author->getLocalizedFamilyName())) {
@@ -906,7 +924,7 @@ protected function setBookAuthors($citationData, $publication, $context): stdCla
         $editorsGroups = $this->getEditorGroups($context->getId());
         $translatorsGroups = $this->getTranslatorGroups($context->getId());
         if (count($authors)) {
-            /** @var \APP\author\Author $author */
+            /** @var Author $author */
             foreach ($authors as $author) {
                 $currentAuthor = new stdClass();
                 if (empty($author->getLocalizedFamilyName())) {
@@ -953,7 +971,7 @@ protected function setBookChapterAuthors($citationData, $publication, $context,
         $chapterAuthorGroups = $this->getChapterAuthorGroups($context->getId());
         $chapterAuthors = $chapter->getAuthors();
 
-        /** @var \APP\author\Author $chapterAuthor */
+        /** @var Author $chapterAuthor */
         foreach ($chapterAuthors as $chapterAuthor) {
             $currentAuthor = new stdClass();
             if (empty($chapterAuthor->getLocalizedFamilyName())) {
@@ -974,7 +992,7 @@ protected function setBookChapterAuthors($citationData, $publication, $context,
         $editorsGroups = $this->getEditorGroups($context->getId());
         $translatorsGroups = $this->getTranslatorGroups($context->getId());
         if (count($bookAuthors)) {
-            /** @var \APP\author\Author $bookAuthor */
+            /** @var Author $bookAuthor */
             foreach ($bookAuthors as $bookAuthor) {
                 $currentAuthor = new stdClass();
                 if (empty($bookAuthor->getLocalizedFamilyName())) {
diff --git a/CitationStyleLanguageSettingsForm.inc.php b/CitationStyleLanguageSettingsForm.php
similarity index 85%
rename from CitationStyleLanguageSettingsForm.inc.php
rename to CitationStyleLanguageSettingsForm.php
index ae7c29e..605bc36 100644
--- a/CitationStyleLanguageSettingsForm.inc.php
+++ b/CitationStyleLanguageSettingsForm.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * @file CitationStyleLanguageSettingsForm.inc.inc.php
+ * @file CitationStyleLanguageSettingsForm.php
  *
  * Copyright (c) 2017-2020 Simon Fraser University
  * Copyright (c) 2017-2020 John Willinsky
@@ -12,12 +12,18 @@
  * @brief Form for site admins to modify Citation Style Language settings.
  */
 
+namespace APP\plugins\generic\citationStyleLanguage;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\template\TemplateManager;
 use PKP\form\Form;
+use PKP\form\validation\FormValidatorCSRF;
+use PKP\form\validation\FormValidatorPost;
 use PKP\notification\PKPNotification;
 use PKP\security\Role;
 
-use APP\notification\NotificationManager;
-
 class CitationStyleLanguageSettingsForm extends Form
 {
     /** @var CitationStyleLanguagePlugin $plugin */
@@ -26,14 +32,14 @@ class CitationStyleLanguageSettingsForm extends Form
     /**
      * Constructor
      *
-     * @param $plugin object
+     * @param CitationStyleLanguagePlugin $plugin object
      */
-    public function __construct($plugin)
+    public function __construct(CitationStyleLanguagePlugin $plugin)
     {
         parent::__construct($plugin->getTemplateResource('settings.tpl'));
         $this->plugin = $plugin;
-        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
-        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+        $this->addCheck(new FormValidatorPost($this));
+        $this->addCheck(new FormValidatorCSRF($this));
     }
 
     /**
@@ -50,7 +56,7 @@ public function initData(): void
         $this->setData('publisherLocation', $this->plugin->getSetting($contextId, 'publisherLocation'));
         $this->setData('groupAuthor', $this->plugin->getAuthorGroups($contextId));
         $this->setData('groupTranslator', $this->plugin->getTranslatorGroups($contextId));
-        if ($this->plugin->isApplicationOmp()) {
+        if ($this->plugin->application === 'omp') {
             $this->setData('groupEditor', $this->plugin->getEditorGroups($contextId));
             $this->setData('groupChapterAuthor', $this->plugin->getChapterAuthorGroups($contextId));
         }
@@ -69,7 +75,7 @@ public function readInputData(): void
             'groupAuthor',
             'groupTranslator'
         ]);
-        if ($this->plugin->isApplicationOmp()) {
+        if ($this->plugin->application === 'omp') {
             $this->readUserVars(['groupEditor']);
             $this->readUserVars(['groupChapterAuthor']);
         }
@@ -96,9 +102,9 @@ public function fetch($request, $template = null, $display = false): ?string
         }
 
         $allUserGroups = [];
-        $userGroupDao = DAORegistry::getDAO('UserGroupDAO'); /* @var $userGroupDao UserGroupDAO */
-        $userGroups = $userGroupDao->getByRoleId( $contextId, Role::ROLE_ID_AUTHOR );
-        while ($userGroup = $userGroups->next()) {
+        $userGroups = Repo::userGroup()->getByRoleIds( [Role::ROLE_ID_AUTHOR], $contextId );
+        $userGroups = $userGroups->toArray();
+        foreach ($userGroups as $userGroup) {
             $allUserGroups[(int) $userGroup->getId()] = $userGroup->getLocalizedName();
         }
         asort($allUserGroups);
@@ -111,13 +117,13 @@ public function fetch($request, $template = null, $display = false): ?string
             'primaryCitationStyle' => $this->getData('primaryCitationStyle'),
             'enabledStyles' => $this->plugin->mapCitationIds($this->plugin->getEnabledCitationStyles($contextId)),
             'enabledDownloads' => $this->plugin->mapCitationIds($this->plugin->getEnabledCitationDownloads($contextId)),
-            'isApplicationOmp' => $this->plugin->isApplicationOmp(),
+            'application' => $this->plugin->application,
             'groupAuthor' => $this->getData('groupAuthor'),
             'groupTranslator' => $this->getData('groupTranslator'),
             'allUserGroups' => $allUserGroups,
         ]);
 
-        if ($this->plugin->isApplicationOmp()) {
+        if ($this->plugin->application === 'omp') {
             $templateMgr->assign([
                 'groupEditor' => $this->getData('groupEditor'),
                 'groupChapterAuthor' => $this->getData('groupChapterAuthor'),
@@ -143,7 +149,7 @@ public function execute(...$functionArgs)
         $this->plugin->updateSetting($contextId, 'publisherLocation', $this->getData('publisherLocation'));
         $this->plugin->updateSetting($contextId, 'groupAuthor', $this->getData('groupAuthor'));
         $this->plugin->updateSetting($contextId, 'groupTranslator', $this->getData('groupTranslator'));
-        if( $this->plugin->isApplicationOmp()) {
+        if( $this->plugin->application === 'omp') {
             $this->plugin->updateSetting($contextId, 'groupEditor', $this->getData('groupEditor'));
             $this->plugin->updateSetting($contextId, 'groupChapterAuthor', $this->getData('groupChapterAuthor'));
         }
diff --git a/index.php b/index.php
index e0db84c..b273e63 100644
--- a/index.php
+++ b/index.php
@@ -13,5 +13,5 @@
  * @brief Wrapper for Citation Style Language plugin.
  *
  */
-require_once('CitationStyleLanguagePlugin.inc.php');
-return new CitationStyleLanguagePlugin();
+require_once('CitationStyleLanguagePlugin.php');
+return new APP\plugins\generic\citationStyleLanguage\CitationStyleLanguagePlugin();
diff --git a/pages/CitationStyleLanguageHandler.inc.php b/pages/CitationStyleLanguageHandler.php
similarity index 91%
rename from pages/CitationStyleLanguageHandler.inc.php
rename to pages/CitationStyleLanguageHandler.php
index 3984088..eafa9c6 100644
--- a/pages/CitationStyleLanguageHandler.inc.php
+++ b/pages/CitationStyleLanguageHandler.php
@@ -1,25 +1,30 @@
 <?php
 
 /**
- * @file plugins/generic/citationStyleLanguage/CitationStyleLanguageHandler.inc.php
+ * @file plugins/generic/citationStyleLanguage/CitationStyleLanguageHandler.php
  *
  * Copyright (c) 2014-2020 Simon Fraser University
  * Copyright (c) 2003-2020 John Willinsky
  * Distributed under the GNU GPL v2 or later. For full terms see the file docs/COPYING.
  *
  * @class CitationStyleLanguageHandler
- * @ingroup plugins_generic_citationstylelanguage
+ * @ingroup plugins_generic_citationStyleLanguage
  *
  * @brief Handle router requests for the citation style language plugin
  */
 
+namespace APP\plugins\generic\citationStyleLanguage\pages;
+
 use APP\facades\Repo;
 use APP\handler\Handler;
-use APP\monograph\Chapter;
 use APP\issue\Issue;
-use APP\submission\Submission;
+use APP\monograph\Chapter;
+use APP\plugins\generic\citationStyleLanguage\CitationStyleLanguagePlugin;
 use APP\publication\Publication;
+use APP\submission\Submission;
 use PKP\core\JSONMessage;
+use PKP\core\PKPRequest;
+use PKP\db\DAORegistry;
 use PKP\plugins\PluginRegistry;
 use PKP\security\Role;
 use PKP\submission\PKPSubmission;
@@ -50,9 +55,9 @@ class CitationStyleLanguageHandler extends Handler
     /**
      * Constructor
      */
-    public function __construct() {
+    public function __construct( CitationStyleLanguagePlugin $plugin ) {
         parent::__construct();
-        $this->plugin = PluginRegistry::getPlugin('generic', 'citationstylelanguageplugin');
+        $this->plugin = $plugin;
     }
 
     /**
@@ -142,7 +147,7 @@ public function _setupRequest($args, $request)
             $this->chapter = $chapterDao->getChapter((int) $userVars['chapterId'], $this->publication->getId());
         }
 
-        if ($this->submission && !$this->plugin->isApplicationOmp()) {
+        if ($this->submission && $this->plugin->application === 'ojs2') {
             // Support OJS 3.1.x and 3.2
             $issueId = method_exists($this->submission, 'getCurrentPublication') ? $this->submission->getCurrentPublication()->getData('issueId') : $this->submission->getIssueId();
             $issue = Repo::issue()->get($issueId);
@@ -154,8 +159,8 @@ public function _setupRequest($args, $request)
         // journal manager or an assigned subeditor or assistant. This ensures the
         // article preview will work for those who can see it.
         if ($this->submission->getStatus() !== PKPSubmission::STATUS_PUBLISHED
-            || (!$this->plugin->isApplicationOmp() && !$this->issue )
-            || (!$this->plugin->isApplicationOmp() && !$this->issue->getPublished())) {
+            || ($this->plugin->application === 'ojs2'
+                && (!$this->issue || !$this->issue->getPublished()))) {
             $userCanAccess = false;
 
             if ($user && $user->hasRole([Role::ROLE_ID_SUB_EDITOR, Role::ROLE_ID_ASSISTANT], $context->getId())) {
diff --git a/templates/settings.tpl b/templates/settings.tpl
index ddcdf15..401d88d 100644
--- a/templates/settings.tpl
+++ b/templates/settings.tpl
@@ -21,7 +21,7 @@
 	{fbvFormArea id="citationStyleLanguagePluginSettings"}
 		{fbvFormSection list=true title="plugins.generic.citationStyleLanguage.settings.citationFormatsPrimary"}
 			<p>
-				{if $isApplicationOmp}
+				{if $application === 'omp'}
 					{translate key="plugins.generic.citationStyleLanguage.settings.citationFormatsPrimaryDescription.omp"}
 				{else}
 					{translate key="plugins.generic.citationStyleLanguage.settings.citationFormatsPrimaryDescription"}
@@ -51,7 +51,7 @@
 					{fbvElement type="checkbox" id="groupAuthor[]" value=$id checked=in_array($id, $groupAuthor) label=$group translate=false}
 				{/foreach}
 			{/fbvFormSection}
-			{if $isApplicationOmp}
+			{if $application === 'omp'}
 				{fbvFormSection list=true label="plugins.generic.citationStyleLanguage.settings.citationChooseChapterAuthor"}
 					<p>{translate key='plugins.generic.citationStyleLanguage.settings.citationOptionChooseChapterAuthor'}</p>
 				{foreach from=$allUserGroups item="group" key="id"}