diff --git a/src/MercadoPago/Entities/OAuth.php b/src/MercadoPago/Entities/OAuth.php
new file mode 100644
index 00000000..0d5a314b
--- /dev/null
+++ b/src/MercadoPago/Entities/OAuth.php
@@ -0,0 +1,82 @@
+<?php
+namespace MercadoPago;
+use MercadoPago\Annotation\RestMethod;
+use MercadoPago\Annotation\Attribute; 
+
+/**
+ * @RestMethod(resource="/oauth/token", method="create")
+ */
+
+class OAuth extends Entity
+{
+   /**
+     * @Attribute()
+     */
+    protected $client_secret;
+    /**
+     * @Attribute()
+     */
+    protected $grant_type;
+    /**
+     * @Attribute()
+     */
+    protected $code;
+    /**
+     * @Attribute()
+     */
+    protected $redirect_uri;
+
+    /**
+     * @Attribute()
+     */
+    protected $access_token;
+    /**
+     * @Attribute()
+     */
+    protected $public_key;
+    /**
+     * @Attribute()
+     */
+    protected $refresh_token;
+    /**
+     * @Attribute()
+     */
+    protected $live_mode;
+    /**
+     * @Attribute()
+     */
+    protected $user_id;
+    /**
+     * @Attribute()
+     */
+    protected $token_type;
+    /**
+     * @Attribute()
+     */
+    protected $expires_in;
+    /**
+     * @Attribute()
+     */
+    protected $scope;
+
+    public function getAuthorizationURL($app_id, $redirect_uri){
+      return "https://auth.mercadopago.com.br/authorization?client_id=${app_id}&response_type=code&platform_id=mp&redirect_uri=${redirect_uri}";
+    }
+
+    public function getOAuthCredentials($authorization_code, $redirect_uri){
+      $this->client_secret = SDK::getAccessToken();
+      $this->grant_type = 'authorization_code';
+      $this->code = $authorization_code;
+      $this->redirect_uri = $redirect_uri;
+
+      return $this->save();
+    }
+
+    public function refreshOAuthCredentials($refresh_token){
+      $this->client_secret = SDK::getAccessToken();
+      $this->grant_type = 'refresh_token';
+      $this->refresh_token = $refresh_token;
+
+      return $this->save();
+    }
+}
diff --git a/src/MercadoPago/Generic/RecuperableError.php b/src/MercadoPago/Generic/RecuperableError.php
index 530b8688..6d6662b6 100644
--- a/src/MercadoPago/Generic/RecuperableError.php
+++ b/src/MercadoPago/Generic/RecuperableError.php
@@ -24,11 +24,15 @@ public function add_cause($code, $description) {
     }
 
     public function proccess_causes($causes){
-        foreach ($causes as $cause){
-            if(is_array($cause) && (!isset($cause['code']) && !isset($cause['description']))){
-                $this->proccess_causes($cause);
-            }else{
-                $this->add_cause($cause['code'], $cause['description']);
+        if(isset($causes['code']) && isset($causes['description'])){
+            $this->add_cause($causes['code'], $causes['description']);
+        }else{
+            foreach ($causes as $cause){
+                if(is_array($cause) && (!isset($cause['code']) && !isset($cause['description']))){
+                    $this->proccess_causes($cause);
+                }else{
+                    $this->add_cause($cause['code'], $cause['description']);
+                }
             }
         }
     }
diff --git a/src/MercadoPago/Manager.php b/src/MercadoPago/Manager.php
index 1ec5fe19..c8081d09 100755
--- a/src/MercadoPago/Manager.php
+++ b/src/MercadoPago/Manager.php
@@ -299,7 +299,9 @@ public function setQueryParams($entity, $urlParams = [])
     protected function _attributesToJson($entity, &$result)
     {
       if (is_array($entity)) {             
-          $attributes = array_filter($entity); 
+          $attributes = array_filter($entity, function($entity) {
+              return ($entity !== null && $entity !== false && $entity !== '');
+          });
       } else { 
           $attributes = $entity->toArray();
       }
@@ -308,7 +310,7 @@ protected function _attributesToJson($entity, &$result)
            if ($value instanceof Entity || is_array($value)) {
                $this->_attributesToJson($value, $result[$key]);
            } else {
-             if ($value != null || is_bool($value)){
+             if ($value != null || is_bool($value) || is_numeric($value)){
                $result[$key] = $value;
              } 
            }