diff --git a/core/modules/book/src/BookOutlineStorageInterface.php b/core/modules/book/src/BookOutlineStorageInterface.php
index c03f3aa..e9b0e0e 100644
--- a/core/modules/book/src/BookOutlineStorageInterface.php
+++ b/core/modules/book/src/BookOutlineStorageInterface.php
@@ -34,10 +34,10 @@ public function hasBooks();
    * @param array $nids
    *   An array of node IDs.
    * @param bool $access
-   *   Whether access checking should be taken into account
+   *   Whether access checking should be taken into account.
    *
-   * @return array Array of loaded book items.
-   * Array of loaded book items.
+   * @return array
+   *   Array of loaded book items.
    */
   public function loadMultiple($nids, $access = TRUE);