diff --git a/modules/custom/dkan_data/src/ValueReferencer.php b/modules/custom/dkan_data/src/ValueReferencer.php
index 44dd8ea7e..cad265791 100644
--- a/modules/custom/dkan_data/src/ValueReferencer.php
+++ b/modules/custom/dkan_data/src/ValueReferencer.php
@@ -282,9 +282,18 @@ protected function dereferenceProperty(string $property_id, $data) {
     if (is_array($data)) {
       return $this->dereferenceMultiple($property_id, $data);
     }
-    else {
+    elseif (is_string($data)) {
       return $this->dereferenceSingle($property_id, $data);
     }
+    else {
+      Drupal::logger('value_referencer')->error(
+        'Unexpected data type when dereferencing property_id @property_id with data "@data"',
+        [
+          '@property_id' => property_id,
+          '@$data' => var_export($data, TRUE),
+        ]
+      );
+    }
   }
 
   /**