diff --git a/src/Form/SourceOverviewForm.php b/src/Form/SourceOverviewForm.php
index a6c94a6..b11ab4d 100644
--- a/src/Form/SourceOverviewForm.php
+++ b/src/Form/SourceOverviewForm.php
@@ -106,8 +106,8 @@ class SourceOverviewForm extends FormBase {
       $plugin_type = $this->sourceManager->createInstance($type);
       $item_types = $plugin_type->getItemTypes();
       asort($item_types);
-      foreach ($item_types as $item_types => $item_label) {
-        $options[(string) $definition['label']][$type . ':' . $item_types] = $item_label;
+      foreach ($item_types as $type_of_item => $item_label) {
+        $options[(string) $definition['label']][$type . ':' . $type_of_item] = $item_label;
       }
     }
     $form['source_type'] = array(