diff --git a/core/modules/book/book.admin.inc b/core/modules/book/book.admin.inc
index f52e44f..bb58871 100644
--- a/core/modules/book/book.admin.inc
+++ b/core/modules/book/book.admin.inc
@@ -5,8 +5,6 @@
  * Administration page callbacks for the Book module.
  */
 
-use Drupal\Core\Entity\EntityInterface;
-
 /**
  * Returns HTML for a book administration form.
  *
diff --git a/core/modules/book/book.module b/core/modules/book/book.module
index 6bf3c83..13c2c96 100644
--- a/core/modules/book/book.module
+++ b/core/modules/book/book.module
@@ -448,7 +448,8 @@ function _book_add_form_elements(&$form, &$form_state, EntityInterface $node) {
 
   $form['book']['plid'] = _book_parent_select($node->book);
 
-  // @see \Drupal\book\Form\BookAdminEditForm::bookAdminTableTree(). The weight may be larger than 15.
+  // @see \Drupal\book\Form\BookAdminEditForm::bookAdminTableTree(). The weight
+  // may be larger than 15.
   $form['book']['weight'] = array(
     '#type' => 'weight',
     '#title' => t('Weight'),
diff --git a/core/modules/book/lib/Drupal/book/Access/OutlineAccessCheck.php b/core/modules/book/lib/Drupal/book/Access/OutlineAccessCheck.php
index 2cd4903..9164501 100644
--- a/core/modules/book/lib/Drupal/book/Access/OutlineAccessCheck.php
+++ b/core/modules/book/lib/Drupal/book/Access/OutlineAccessCheck.php
@@ -17,14 +17,14 @@
 class OutlineAccessCheck implements AccessCheckInterface {
 
   /**
-   * Implements AccessCheckInterface::applies().
+   * {@inheritdoc}
    */
   public function applies(Route $route) {
     return array_key_exists('_book_outline_access', $route->getRequirements());
   }
 
   /**
-   * Implements AccessCheckInterface::access().
+   * {@inheritdoc}
    */
   public function access(Route $route, Request $request) {
     return user_access('administer book outlines') && node_access('view', $request->attributes->get('node'));