diff --git a/lib/Ebook.php b/lib/Ebook.php
index 1670c597..0170e7d2 100644
--- a/lib/Ebook.php
+++ b/lib/Ebook.php
@@ -935,6 +935,9 @@ class Ebook{
 	// ORM METHODS
 	// ***********
 
+	/**
+	 * @throws \Exceptions\EbookNotFoundException
+	 */
 	public static function GetByIdentifier(?string $identifier): Ebook{
 		if($identifier === null){
 			throw new Exceptions\EbookNotFoundException('Invalid identifier: ' . $identifier);