diff --git a/src/Normalizer/EntityReferenceFieldNormalizer.php b/src/Normalizer/EntityReferenceFieldNormalizer.php
index 8b9dad2..baab98c 100644
--- a/src/Normalizer/EntityReferenceFieldNormalizer.php
+++ b/src/Normalizer/EntityReferenceFieldNormalizer.php
@@ -86,9 +86,10 @@ class EntityReferenceFieldNormalizer extends FieldNormalizer implements Denormal
       ->getFieldStorageDefinition()
       ->getCardinality();
     $entity_collection = new EntityCollection(array_map(function ($item) {
-      if ($entity = $item->get('entity')->getValue()) {
-        return $this->entityRepository->getTranslationFromContext($entity);
-      }
+      // Get the referenced entity.
+      $entity = $item->get('entity')->getValue();
+      // And get the translation in the requested language.
+      return $this->entityRepository->getTranslationFromContext($entity);
     }, (array) $field->getIterator()));
     $relationship = new Relationship($this->resourceTypeRepository, $field->getName(), $cardinality, $entity_collection, $field->getEntity(), $main_property);
     return $this->serializer->normalize($relationship, $format, $context);
diff --git a/tests/src/Functional/JsonApiFunctionalBaseTest.php b/tests/src/Functional/JsonApiFunctionalBaseTest.php
new file mode 100644
index 0000000..21664ab
--- /dev/null
+++ b/tests/src/Functional/JsonApiFunctionalBaseTest.php
@@ -0,0 +1,280 @@
+<?php
+
+namespace Drupal\Tests\jsonapi\Functional;
+
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
+use Drupal\Core\Url;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\field\Tests\EntityReference\EntityReferenceTestTrait;
+use Drupal\file\Entity\File;
+use Drupal\taxonomy\Entity\Term;
+use Drupal\taxonomy\Entity\Vocabulary;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\image\Kernel\ImageFieldCreationTrait;
+use Drupal\user\Entity\Role;
+use Drupal\user\RoleInterface;
+use GuzzleHttp\Exception\ClientException;
+use GuzzleHttp\Exception\ServerException;
+
+/**
+ * @group jsonapi
+ */
+abstract class JsonApiFunctionalBaseTest extends BrowserTestBase {
+
+  use EntityReferenceTestTrait;
+  use ImageFieldCreationTrait;
+
+  const IS_MULTILINGUAL = TRUE;
+  const IS_NOT_MULTILINGUAL = FALSE;
+
+  public static $modules = [
+    'basic_auth',
+    'jsonapi',
+    'serialization',
+    'node',
+    'image',
+    'taxonomy',
+    'link',
+  ];
+
+  /**
+   * @var \Drupal\user\Entity\User
+   */
+  protected $user;
+
+  /**
+   * @var \Drupal\user\Entity\User
+   */
+  protected $userCanViewProfiles;
+
+  /**
+   * @var \Drupal\node\Entity\Node[]
+   */
+  protected $nodes = [];
+
+  /**
+   * @var \Drupal\taxonomy\Entity\Term[]
+   */
+  protected $tags = [];
+
+  /**
+   * @var \Drupal\file\Entity\File[]
+   */
+  protected $files = [];
+
+  /**
+   * @var \GuzzleHttp\ClientInterface
+   */
+  protected $httpClient;
+
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Set up a HTTP client that accepts relative URLs.
+    $this->httpClient = $this->container->get('http_client_factory')
+      ->fromOptions(['base_uri' => $this->baseUrl]);
+
+    // Create Basic page and Article node types.
+    if ($this->profile != 'standard') {
+      $this->drupalCreateContentType(array(
+        'type' => 'article',
+        'name' => 'Article',
+      ));
+
+      // Setup vocabulary.
+      Vocabulary::create([
+        'vid' => 'tags',
+        'name' => 'Tags',
+      ])->save();
+
+      // Add tags and field_image to the article.
+      $this->createEntityReferenceField(
+        'node',
+        'article',
+        'field_tags',
+        'Tags',
+        'taxonomy_term',
+        'default',
+        [
+          'target_bundles' => [
+            'tags' => 'tags',
+          ],
+          'auto_create' => TRUE,
+        ],
+        FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED
+      );
+      $this->createImageField('field_image', 'article');
+    }
+
+    FieldStorageConfig::create(array(
+      'field_name' => 'field_link',
+      'entity_type' => 'node',
+      'type' => 'link',
+      'settings' => [],
+      'cardinality' => 1,
+    ))->save();
+
+    $field_config = FieldConfig::create([
+      'field_name' => 'field_link',
+      'label' => 'Link',
+      'entity_type' => 'node',
+      'bundle' => 'article',
+      'required' => FALSE,
+      'settings' => [],
+      'description' => '',
+    ]);
+    $field_config->save();
+
+    $this->user = $this->drupalCreateUser([
+      'create article content',
+      'edit any article content',
+      'delete any article content',
+    ]);
+
+    // Create a user that can
+    $this->userCanViewProfiles = $this->drupalCreateUser([
+      'access user profiles',
+    ]);
+
+    $this->grantPermissions(Role::load(RoleInterface::ANONYMOUS_ID), [
+      'access user profiles',
+      'administer taxonomy',
+    ]);
+
+    drupal_flush_all_caches();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function drupalGet($path, array $options = array(), array $headers = array()) {
+    // Make sure we don't forget the format parameter.
+    $options += ['query' => []];
+    $options['query'] += ['_format' => 'api_json'];
+
+    return parent::drupalGet($path, $options, $headers);
+  }
+
+  /**
+   * Performs a HTTP request. Wraps the Guzzle HTTP client.
+   *
+   * Why wrap the Guzzle HTTP client? Because any error response is returned via
+   * an exception, which would make the tests unnecessarily complex to read.
+   *
+   * @see \GuzzleHttp\ClientInterface::request()
+   *
+   * @param string $method
+   *   HTTP method.
+   * @param \Drupal\Core\Url $url
+   *   URL to request.
+   * @param array $request_options
+   *   Request options to apply.
+   *
+   * @return \Psr\Http\Message\ResponseInterface
+   */
+  protected function request($method, Url $url, array $request_options) {
+    $url->setOption('query', ['_format' => 'api_json']);
+    try {
+      $response = $this->httpClient->request($method, $url->toString(), $request_options);
+    }
+    catch (ClientException $e) {
+      $response = $e->getResponse();
+    }
+    catch (ServerException $e) {
+      $response = $e->getResponse();
+    }
+
+    return $response;
+  }
+
+  /**
+   * Creates default content to test the API.
+   *
+   * @param int $num_articles
+   *   Number of articles to create.
+   * @param int $num_tags
+   *   Number of tags to create.
+   * @param bool $article_has_image
+   *   Set to TRUE if you want to add an image to the generated articles.
+   * @param bool $article_has_link
+   *   Set to TRUE if you want to add a link to the generated articles.
+   * @param bool $is_multilingual
+   *   (optional) Set to TRUE if you want to enable multilingual content.
+   */
+  protected function createDefaultContent($num_articles, $num_tags, $article_has_image, $article_has_link, $is_multilingual) {
+    $random = $this->getRandomGenerator();
+    for ($created_tags = 0; $created_tags < $num_tags; $created_tags++) {
+      $term = Term::create([
+        'vid' => 'tags',
+        'name' => $random->name(),
+      ]);
+
+      if ($is_multilingual) {
+        $term->addTranslation('ca', ['name' => $term->getName() . ' (ca)']);
+      }
+
+      $term->save();
+      $this->tags[] = $term;
+    }
+    for ($created_nodes = 0; $created_nodes < $num_articles; $created_nodes++) {
+      // Get N random tags.
+      $selected_tags = mt_rand(1, $num_tags);
+      $tags = [];
+      while (count($tags) < $selected_tags) {
+        $tags[] = mt_rand(1, $num_tags);
+        $tags = array_unique($tags);
+      }
+      $values = [
+        'uid' => ['target_id' => $this->user->id()],
+        'type' => 'article',
+        'field_tags' => array_map(function ($tag) {
+          return ['target_id' => $tag];
+        }, $tags),
+      ];
+      if ($article_has_image) {
+        $file = File::create([
+          'uri' => 'vfs://' . $random->name() . '.png',
+        ]);
+        $file->setPermanent();
+        $file->save();
+        $this->files[] = $file;
+        $values['field_image'] = ['target_id' => $file->id(), 'alt' => 'alt text'];
+      }
+      if ($article_has_link) {
+        $values['field_link'] = [
+          'title' => $this->getRandomGenerator()->name(),
+          'uri' => sprintf(
+            '%s://%s.%s',
+            'http' . (mt_rand(0, 2) > 1 ? '' : 's'),
+            $this->getRandomGenerator()->name(),
+            'org'
+          ),
+        ];
+      }
+      $node = $this->createNode($values);
+
+      if ($is_multilingual === static::IS_MULTILINGUAL) {
+        $values['title'] = $node->getTitle() . ' (ca)';
+        $values['field_image']['alt'] = 'alt text (ca)';
+        $node->addTranslation('ca', $values);
+      }
+      $node->save();
+
+      $this->nodes[] = $node;
+    }
+    if ($article_has_link) {
+      // Make sure that there is at least 1 https link for ::testRead() #19.
+      $this->nodes[0]->field_link = [
+        'title' => 'Drupal',
+        'uri' => 'https://drupal.org'
+      ];
+      $this->nodes[0]->save();
+    }
+  }
+
+}
diff --git a/tests/src/Functional/JsonApiFunctionalMultilingualTest.php b/tests/src/Functional/JsonApiFunctionalMultilingualTest.php
new file mode 100644
index 0000000..3e27e4f
--- /dev/null
+++ b/tests/src/Functional/JsonApiFunctionalMultilingualTest.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace Drupal\Tests\jsonapi\Functional;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\language\Entity\ConfigurableLanguage;
+
+/**
+ * @group jsonapi
+ */
+class JsonApiFunctionalMultilingualTest extends JsonApiFunctionalBaseTest {
+
+  public static $modules = [
+    'basic_auth',
+    'jsonapi',
+    'serialization',
+    'node',
+    'image',
+    'taxonomy',
+    'link',
+    'language',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $language = ConfigurableLanguage::createFromLangcode('ca');
+    $language->save();
+
+    // In order to reflect the changes for a multilingual site in the container
+    // we have to rebuild it.
+    $this->rebuildContainer();
+
+    \Drupal::configFactory()->getEditable('language.negotiation')
+      ->set('url.prefixes.ca', 'ca')
+      ->save();
+  }
+
+  /**
+   * Tests reading multilingual content.
+   */
+  public function testReadMultilingual() {
+    $this->createDefaultContent(5, 5, TRUE, TRUE, static::IS_MULTILINGUAL);
+
+    // Test reading an individual entity.
+    $output = Json::decode($this->drupalGet('/ca/jsonapi/node/article/' . $this->nodes[0]->uuid(), ['query' => ['include' => 'field_tags,field_image']]));
+    $this->assertEquals($this->nodes[0]->getTranslation('ca')->getTitle(), $output['data']['attributes']['title']);
+
+    $included_tags = array_filter($output['included'], function ($entry) {
+      return $entry['type'] === 'taxonomy_term--tags';
+    });
+    $tag_name = $this->nodes[0]->get('field_tags')->entity
+      ->getTranslation('ca')->getName();
+    // TODO figure out how to fetcht the alt text of an image.
+    $this->assertEquals($tag_name, reset($included_tags)['attributes']['name']);
+
+    $output = Json::decode($this->drupalGet('/ca/jsonapi/node/article/' . $this->nodes[0]->uuid()));
+    $this->assertEquals($this->nodes[0]->getTranslation('ca')->getTitle(), $output['data']['attributes']['title']);
+
+    // Test reading a collection of entities.
+    $output = Json::decode($this->drupalGet('/ca/jsonapi/node/article'));
+    $this->assertEquals($this->nodes[0]->getTranslation('ca')->getTitle(), $output['data'][0]['attributes']['title']);
+  }
+
+}
diff --git a/tests/src/Functional/JsonApiFunctionalTest.php b/tests/src/Functional/JsonApiFunctionalTest.php
index 8aaa779..2555d57 100644
--- a/tests/src/Functional/JsonApiFunctionalTest.php
+++ b/tests/src/Functional/JsonApiFunctionalTest.php
@@ -3,197 +3,13 @@
 namespace Drupal\Tests\jsonapi\Functional;
 
 use Drupal\Component\Serialization\Json;
-use Drupal\Core\Field\FieldStorageDefinitionInterface;
 use Drupal\Core\Url;
-use Drupal\field\Entity\FieldConfig;
-use Drupal\field\Entity\FieldStorageConfig;
-use Drupal\field\Tests\EntityReference\EntityReferenceTestTrait;
-use Drupal\file\Entity\File;
 use Drupal\jsonapi\Routing\Param\OffsetPage;
-use Drupal\language\Entity\ConfigurableLanguage;
-use Drupal\taxonomy\Entity\Term;
-use Drupal\taxonomy\Entity\Vocabulary;
-use Drupal\Tests\BrowserTestBase;
-use Drupal\Tests\image\Kernel\ImageFieldCreationTrait;
-use Drupal\user\Entity\Role;
-use Drupal\user\RoleInterface;
-use GuzzleHttp\Exception\ClientException;
-use GuzzleHttp\Exception\ServerException;
 
 /**
  * @group jsonapi
  */
-class JsonApiFunctionalTest extends BrowserTestBase {
-
-  use EntityReferenceTestTrait;
-  use ImageFieldCreationTrait;
-
-  const IS_MULTILINGUAL = TRUE;
-  const IS_NOT_MULTILINGUAL = FALSE;
-
-  public static $modules = [
-    'basic_auth',
-    'jsonapi',
-    'serialization',
-    'node',
-    'image',
-    'taxonomy',
-    'link',
-  ];
-
-  /**
-   * @var \Drupal\user\Entity\User
-   */
-  protected $user;
-
-  /**
-   * @var \Drupal\user\Entity\User
-   */
-  protected $userCanViewProfiles;
-
-  /**
-   * @var \Drupal\node\Entity\Node[]
-   */
-  protected $nodes = [];
-
-  /**
-   * @var \Drupal\taxonomy\Entity\Term[]
-   */
-  protected $tags = [];
-
-  /**
-   * @var \Drupal\file\Entity\File[]
-   */
-  protected $files = [];
-
-  /**
-   * @var \GuzzleHttp\ClientInterface
-   */
-  protected $httpClient;
-
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-
-    // Set up a HTTP client that accepts relative URLs.
-    $this->httpClient = $this->container->get('http_client_factory')
-      ->fromOptions(['base_uri' => $this->baseUrl]);
-
-    // Create Basic page and Article node types.
-    if ($this->profile != 'standard') {
-      $this->drupalCreateContentType(array(
-        'type' => 'article',
-        'name' => 'Article',
-      ));
-
-      // Setup vocabulary.
-      Vocabulary::create([
-        'vid' => 'tags',
-        'name' => 'Tags',
-      ])->save();
-
-      // Add tags and field_image to the article.
-      $this->createEntityReferenceField(
-        'node',
-        'article',
-        'field_tags',
-        'Tags',
-        'taxonomy_term',
-        'default',
-        [
-          'target_bundles' => [
-            'tags' => 'tags',
-          ],
-          'auto_create' => TRUE,
-        ],
-        FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED
-      );
-      $this->createImageField('field_image', 'article');
-    }
-
-    FieldStorageConfig::create(array(
-      'field_name' => 'field_link',
-      'entity_type' => 'node',
-      'type' => 'link',
-      'settings' => [],
-      'cardinality' => 1,
-    ))->save();
-
-    $field_config = FieldConfig::create([
-      'field_name' => 'field_link',
-      'label' => 'Link',
-      'entity_type' => 'node',
-      'bundle' => 'article',
-      'required' => FALSE,
-      'settings' => [],
-      'description' => '',
-    ]);
-    $field_config->save();
-
-    $this->user = $this->drupalCreateUser([
-      'create article content',
-      'edit any article content',
-      'delete any article content',
-    ]);
-
-    // Create a user that can
-    $this->userCanViewProfiles = $this->drupalCreateUser([
-      'access user profiles',
-    ]);
-
-    $this->grantPermissions(Role::load(RoleInterface::ANONYMOUS_ID), [
-      'access user profiles',
-      'administer taxonomy',
-    ]);
-
-    drupal_flush_all_caches();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function drupalGet($path, array $options = array(), array $headers = array()) {
-    // Make sure we don't forget the format parameter.
-    $options += ['query' => []];
-    $options['query'] += ['_format' => 'api_json'];
-
-    return parent::drupalGet($path, $options, $headers);
-  }
-
-  /**
-   * Performs a HTTP request. Wraps the Guzzle HTTP client.
-   *
-   * Why wrap the Guzzle HTTP client? Because any error response is returned via
-   * an exception, which would make the tests unnecessarily complex to read.
-   *
-   * @see \GuzzleHttp\ClientInterface::request()
-   *
-   * @param string $method
-   *   HTTP method.
-   * @param \Drupal\Core\Url $url
-   *   URL to request.
-   * @param array $request_options
-   *   Request options to apply.
-   *
-   * @return \Psr\Http\Message\ResponseInterface
-   */
-  protected function request($method, Url $url, array $request_options) {
-    $url->setOption('query', ['_format' => 'api_json']);
-    try {
-      $response = $this->httpClient->request($method, $url->toString(), $request_options);
-    }
-    catch (ClientException $e) {
-      $response = $e->getResponse();
-    }
-    catch (ServerException $e) {
-      $response = $e->getResponse();
-    }
-
-    return $response;
-  }
+class JsonApiFunctionalTest extends JsonApiFunctionalBaseTest {
 
   /**
    * Test the GET method.
@@ -418,34 +234,6 @@ class JsonApiFunctionalTest extends BrowserTestBase {
   }
 
   /**
-   * Tests reading multilingual content.
-   */
-  public function testReadMultilingual() {
-    $this->setupMultilingual();
-
-    $this->createDefaultContent(5, 5, TRUE, TRUE, static::IS_MULTILINGUAL);
-
-    // Test reading an individual entity.
-    $output = Json::decode($this->drupalGet('/es/jsonapi/node/article/' . $this->nodes[0]->uuid(), ['query' => ['include' => 'field_tags,field_image']]));
-    $this->assertEquals($this->nodes[0]->getTranslation('es')->getTitle(), $output['data']['attributes']['title']);
-
-    $included_tags = array_filter($output['included'], function ($entry) {
-      return $entry['type'] === 'taxonomy_term--tags';
-    });
-    $this->assertEquals($this->nodes[0]->get('field_tags')->entity->getTranslation('es')->getName(), reset($included_tags)['attributes']['name']);
-    // @todo figure out how to fetcht the alt text of an image.
-
-    $output = Json::decode($this->drupalGet('/es/jsonapi/node/article/' . $this->nodes[0]->uuid()));
-    $this->assertEquals($this->nodes[0]->getTranslation('es')->getTitle(), $output['data']['attributes']['title']);
-
-    // Test reading a collection of entities.
-
-    $output = Json::decode($this->drupalGet('/es/jsonapi/node/article'));
-    $this->assertEquals($this->nodes[0]->getTranslation('es')->getTitle(), $output['data'][0]['attributes']['title']);
-  }
-
-
-  /**
    * Test POST, PATCH and DELETE.
    */
   public function testWrite() {
@@ -728,106 +516,4 @@ class JsonApiFunctionalTest extends BrowserTestBase {
     $this->assertEquals(404, $response->getStatusCode());
   }
 
-  /**
-   * Creates default content to test the API.
-   *
-   * @param int $num_articles
-   *   Number of articles to create.
-   * @param int $num_tags
-   *   Number of tags to create.
-   * @param bool $article_has_image
-   *   Set to TRUE if you want to add an image to the generated articles.
-   * @param bool $article_has_link
-   *   Set to TRUE if you want to add a link to the generated articles.
-   * @param bool $is_multilingual
-   *   (optional) Set to TRUE if you want to enable multilingual content.
-   */
-  protected function createDefaultContent($num_articles, $num_tags, $article_has_image, $article_has_link, $is_multilingual) {
-    $random = $this->getRandomGenerator();
-    for ($created_tags = 0; $created_tags < $num_tags; $created_tags++) {
-      $term = Term::create([
-        'vid' => 'tags',
-        'name' => $random->name(),
-      ]);
-
-      if ($is_multilingual) {
-        $term->addTranslation('es', ['name' => $term->getName() . ' (es)']);
-      }
-
-      $term->save();
-      $this->tags[] = $term;
-    }
-    for ($created_nodes = 0; $created_nodes < $num_articles; $created_nodes++) {
-      // Get N random tags.
-      $selected_tags = mt_rand(1, $num_tags);
-      $tags = [];
-      while (count($tags) < $selected_tags) {
-        $tags[] = mt_rand(1, $num_tags);
-        $tags = array_unique($tags);
-      }
-      $values = [
-        'uid' => ['target_id' => $this->user->id()],
-        'type' => 'article',
-        'field_tags' => array_map(function ($tag) {
-          return ['target_id' => $tag];
-        }, $tags),
-      ];
-      if ($article_has_image) {
-        $file = File::create([
-          'uri' => 'vfs://' . $random->name() . '.png',
-        ]);
-        $file->setPermanent();
-        $file->save();
-        $this->files[] = $file;
-        $values['field_image'] = ['target_id' => $file->id(), 'alt' => 'alt text'];
-      }
-      if ($article_has_link) {
-        $values['field_link'] = [
-          'title' => $this->getRandomGenerator()->name(),
-          'uri' => sprintf(
-            '%s://%s.%s',
-            'http' . (mt_rand(0, 2) > 1 ? '' : 's'),
-            $this->getRandomGenerator()->name(),
-            'org'
-          ),
-        ];
-      }
-      $node = $this->createNode($values);
-
-      if ($is_multilingual === static::IS_MULTILINGUAL) {
-        $values['title'] = $node->getTitle() . ' (es)';
-        $values['field_image']['alt'] = 'alt text (es)';
-        $node->addTranslation('es', $values);
-      }
-      $node->save();
-
-      $this->nodes[] = $node;
-    }
-    if ($article_has_link) {
-      // Make sure that there is at least 1 https link for ::testRead() #19.
-      $this->nodes[0]->field_link = [
-        'title' => 'Drupal',
-        'uri' => 'https://drupal.org'
-      ];
-      $this->nodes[0]->save();
-    }
-  }
-
-  /**
-   * Setup the multilingual configuration.
-   */
-  protected function setupMultilingual() {
-    $this->container->get('module_installer')->install(['language']);
-    $language = ConfigurableLanguage::createFromLangcode('es');
-    $language->save();
-
-    // In order to reflect the changes for a multilingual site in the container
-    // we have to rebuild it.
-    $this->rebuildContainer();
-
-    \Drupal::configFactory()->getEditable('language.negotiation')
-      ->set('url.prefixes.es', 'es')
-      ->save();
-  }
-
 }