diff --git a/src/Normalizer/EntityReferenceFieldNormalizer.php b/src/Normalizer/EntityReferenceFieldNormalizer.php
index c7aea2c..7795c37 100644
--- a/src/Normalizer/EntityReferenceFieldNormalizer.php
+++ b/src/Normalizer/EntityReferenceFieldNormalizer.php
@@ -86,18 +86,18 @@ class EntityReferenceFieldNormalizer extends FieldNormalizer implements Denormal
       ->getFieldStorageDefinition()
       ->getCardinality();
     /** @var \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem[] $entity_reference_item_list */
-    $entity_reference_item_list = array_filter($field->getIterator()->getArrayCopy(), function ($item) {
+    $entity_reference_item_list = array_filter(iterator_to_array($field), function ($item) {
       return (bool) $item->get('entity')->getValue();
     });
-    $entity_list_metadata = array();
-    $entity_list = array();
+    $entity_list_metadata = [];
+    $entity_list = [];
     foreach ($entity_reference_item_list as $item) {
       // Prepare a list of additional properties stored by the field.
-      $metadata = array();
+      $metadata = [];
       /** @var \Drupal\Core\TypedData\TypedDataInterface[] $properties */
       $properties = $item->getProperties();
       foreach ($properties as $property_key => $property) {
-        if ($property_key != $main_property) {
+        if ($property_key !== $main_property) {
           $metadata[$property_key] = $property->getValue();
         }
       }
diff --git a/src/Normalizer/RelationshipItem.php b/src/Normalizer/RelationshipItem.php
index b031fad..c658838 100644
--- a/src/Normalizer/RelationshipItem.php
+++ b/src/Normalizer/RelationshipItem.php
@@ -97,9 +97,8 @@ class RelationshipItem {
    */
   public function getValue() {
     return [
-      $this->targetKey => $this->getTargetEntity()->uuid(),
+      'target_uuid' => $this->getTargetEntity()->uuid(),
       'meta' => $this->metadata,
-      'target_key' => $this->targetKey,
     ];
   }
 
diff --git a/src/Normalizer/Value/RelationshipItemNormalizerValue.php b/src/Normalizer/Value/RelationshipItemNormalizerValue.php
index d37ab5c..3a180aa 100644
--- a/src/Normalizer/Value/RelationshipItemNormalizerValue.php
+++ b/src/Normalizer/Value/RelationshipItemNormalizerValue.php
@@ -41,7 +41,7 @@ class RelationshipItemNormalizerValue extends FieldItemNormalizerValue implement
     }
     $rasterizedValue = [
       'type' => $this->resource->getTypeName(),
-      'id' => is_array($value) ? $value[$value['target_key']] : $value,
+      'id' => is_array($value) ? $value['target__uuid'] : $value,
     ];
 
     if (!empty($value['meta'])) {