diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index f9f633f..8a067b5 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -339,6 +339,14 @@ class Configuration implements ConfigurationInterface
             ->scalarNode('index_options')->end()
             ->scalarNode('ignore_above')->end()
             ->scalarNode('position_offset_gap')->end()
+            ->arrayNode('_parent')
+                ->treatNullLike(array())
+                ->children()
+                    ->scalarNode('type')->end()
+                    ->scalarNode('identifier')->defaultValue('id')->end()
+                ->end()
+            ->end()
+            ->scalarNode('format')->end();
         ;
 
         if (isset($nestings['fields'])) {
diff --git a/Finder/TransformedFinder.php b/Finder/TransformedFinder.php
index e0b9cd0..123aba6 100644
--- a/Finder/TransformedFinder.php
+++ b/Finder/TransformedFinder.php
@@ -45,6 +45,22 @@ class TransformedFinder implements PaginatedFinderInterface
         return $this->transformer->hybridTransform($results);
     }
 
+    /**
+     * Find documents similar to one with passed id.
+     *
+     * @param integer $id
+     * @param array $params
+     * @param array $query
+     * @return array of model objects
+     **/
+    public function moreLikeThis($id, $params = array(), $query = array())
+    {
+        $doc = new Document($id);
+        $results = $this->searchable->moreLikeThis($doc, $params, $query)->getResults();
+
+        return $this->transformer->transform($results);
+    }
+
     /**
      * @param $query
      * @param null|int $limit
diff --git a/README.md b/README.md
index 22d4100..e132a15 100644
--- a/README.md
+++ b/README.md
@@ -102,9 +102,9 @@ Here we created a "website" index, that uses our "default" client.
 
 Our index is now available as a service: `fos_elastica.index.website`. It is an instance of `\Elastica\Index`.
 
-If you need to have different index name from the service name, for example, 
-in order to have different indexes for different environments then you can 
-use the ```index_name``` key to change the index name. The service name will 
+If you need to have different index name from the service name, for example,
+in order to have different indexes for different environments then you can
+use the ```index_name``` key to change the index name. The service name will
 remain the same across the environments:
 
     fos_elastica:
@@ -114,8 +114,8 @@ remain the same across the environments:
             website:
                 client: default
                 index_name: website_qa
-                
-The service id will be `fos_elastica.index.website` but the underlying index name is website_qa.           
+
+The service id will be `fos_elastica.index.website` but the underlying index name is website_qa.
 
 #### Declare a type
 
@@ -796,3 +796,21 @@ $term = new \Elastica\Filter\Term(array('active' => true));
 $filteredQuery = new \Elastica\Query\Filtered($query, $term);
 $results = $this->container->get('fos_elastica.finder.index.type')->find($filteredQuery);
 ```
+
+### Date format example
+
+If you want to specify a [date format](http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/mapping-date-format.html):
+
+```yaml
+fos_elastica:
+    clients:
+        default: { host: localhost, port: 9200 }
+    indexes:
+        site:
+            types:
+                user:
+                    mappings:
+                        username: { type: string }
+                        lastlogin: { type: date, format: basic_date_time }
+                        birthday: { type: date, format: "yyyy-MM-dd" }
+```
diff --git a/Tests/DependencyInjection/ConfigurationTest.php b/Tests/DependencyInjection/ConfigurationTest.php
new file mode 100644
index 0000000..f410621
--- /dev/null
+++ b/Tests/DependencyInjection/ConfigurationTest.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace FOS\ElasticaBundle\Tests\Resetter\DependencyInjection;
+
+use FOS\ElasticaBundle\DependencyInjection\Configuration;
+
+/**
+ * ConfigurationTest
+ */
+class ConfigurationTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var Configuration
+     */
+    private $configuration;
+
+    public function setUp()
+    {
+        $this->configuration = new Configuration(array());
+    }
+
+    public function testEmptyConfigContainsFormatMappingOptionNode()
+    {
+        $tree = $this->configuration->getConfigTree();
+        $children = $tree->getChildren();
+        $children = $children['indexes']->getPrototype()->getChildren();
+        $typeNodes = $children['types']->getPrototype()->getChildren();
+        $mappings = $typeNodes['mappings']->getPrototype()->getChildren();
+
+        $this->assertArrayHasKey('format', $mappings);
+        $this->assertInstanceOf('Symfony\Component\Config\Definition\ScalarNode', $mappings['format']);
+        $this->assertNull($mappings['format']->getDefaultValue());
+    }
+}