diff --git a/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php b/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
index 68529bdf74ac378d5da08a1ce8ccbdd3e16be8e5..10fdca54af42916b9babf0a92a939648405371f7 100644
--- a/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
+++ b/module/VuFind/src/VuFind/RecordDriver/SolrDefault.php
@@ -1056,8 +1056,8 @@ class SolrDefault extends AbstractBase
      */
     public function getPrimaryAuthors()
     {
-        return isset($this->fields['author']) ?
-            $this->fields['author'] : [];
+        return isset($this->fields['author'])
+            ? (array) $this->fields['author'] : [];
     }
 
     /**