diff --git a/src/ZugferdDocument.php b/src/ZugferdDocument.php
index 9f6f86fe..7238e773 100644
--- a/src/ZugferdDocument.php
+++ b/src/ZugferdDocument.php
@@ -76,7 +76,7 @@ class ZugferdDocument
      *
      * @codeCoverageIgnore
      */
-    protected function __construct(int $profile)
+    final protected function __construct(int $profile)
     {
         $this->initProfile($profile);
         $this->initObjectHelper();
@@ -87,7 +87,7 @@ protected function __construct(int $profile)
      * Returns the internal invoice object (created by the
      * serializer). This is used e.g. in the validator
      *
-     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwö\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
+     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwl\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
      */
     public function getInvoiceObject()
     {
@@ -97,7 +97,7 @@ public function getInvoiceObject()
     /**
      * Create a new instance of the internal invoice object
      *
-     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwö\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
+     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwl\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
      */
     protected function createInvoiceObject()
     {
@@ -273,7 +273,7 @@ function (HandlerRegistryInterface $handler) {
      * Deserialize XML content to internal invoice object
      *
      * @param string $xmlContent
-     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwö\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
+     * @return \horstoeko\zugferd\entities\basic\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\basicwl\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\en16931\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\extended\rsm\CrossIndustryInvoice|\horstoeko\zugferd\entities\minimum\rsm\CrossIndustryInvoice
      */
     public function deserialize($xmlContent)
     {