diff --git a/src/Entity/SubMerchantInfo.php b/src/Entity/SubMerchantInfo.php
index <HASH>..<HASH> 100644
--- a/src/Entity/SubMerchantInfo.php
+++ b/src/Entity/SubMerchantInfo.php
@@ -36,6 +36,8 @@ namespace Wirecard\PaymentSdk\Entity;
  * @package Wirecard\PaymentSdk\Entity
  *
  * An immutable entity representing a SubMerchant.
+ *
+ * @since 2.3.0
  */
 class SubMerchantInfo implements MappableEntity
 {
diff --git a/src/Transaction/WeChatTransaction.php b/src/Transaction/WeChatTransaction.php
index <HASH>..<HASH> 100644
--- a/src/Transaction/WeChatTransaction.php
+++ b/src/Transaction/WeChatTransaction.php
@@ -35,6 +35,11 @@ use Wirecard\PaymentSdk\Entity\SubMerchantInfo;
 use Wirecard\PaymentSdk\Exception\MandatoryFieldMissingException;
 use Wirecard\PaymentSdk\Exception\UnsupportedOperationException;
 
+/**
+ * Class WeChatTransaction
+ * @package Wirecard\PaymentSdk\Transaction
+ * @since 2.3.0
+ */
 class WeChatTransaction extends Transaction implements Reservable
 {
     const NAME = 'wechat-qrpay';
#<I> add since annotations to class headers