diff --git a/src/Database.php b/src/Database.php
index b8556ff..7b54da3 100644
--- a/src/Database.php
+++ b/src/Database.php
@@ -219,17 +219,17 @@ class Database
      * Get a single record.
      *
      * @param string $identifier The record identifier
-     * @param string $metadataPrefix The metadata prefix
+     * @param Format $format The metadata format
      *
      * @return ?Record The record or NULL on failure
      */
-    public function getRecord(string $identifier, string $metadataPrefix): ?Record
+    public function getRecord(string $identifier, Format $format): ?Record
     {
         return $this->entityManager->find(
             Record::class,
             [
                 'identifier' => $identifier,
-                'format' => $metadataPrefix
+                'format' => $format
             ]
         );
     }
diff --git a/src/Middleware/GetRecord.php b/src/Middleware/GetRecord.php
index 607670b..6249d20 100644
--- a/src/Middleware/GetRecord.php
+++ b/src/Middleware/GetRecord.php
@@ -23,6 +23,7 @@ declare(strict_types=1);
 namespace OCC\OaiPmh2\Middleware;
 
 use OCC\OaiPmh2\Database;
+use OCC\OaiPmh2\Database\Format;
 use OCC\OaiPmh2\Document;
 use OCC\OaiPmh2\Middleware;
 use Psr\Http\Message\ServerRequestInterface;
@@ -46,7 +47,9 @@ class GetRecord extends Middleware
     protected function prepareResponse(ServerRequestInterface $request): void
     {
         $params = $request->getAttributes();
-        $oaiRecord = Database::getInstance()->getRecord($params['identifier'], $params['metadataPrefix']);
+        /** @var Format */
+        $format = Database::getInstance()->getEntityManager()->getReference(Format::class, $params['metadataPrefix']);
+        $oaiRecord = Database::getInstance()->getRecord($params['identifier'], $format);
 
         if (!isset($oaiRecord)) {
             if (Database::getInstance()->idDoesExist($params['identifier'])) {