diff --git a/Document-Processing/PDF/PDF-Library/NET/Working-with-ZUGFeRD-invoice.md b/Document-Processing/PDF/PDF-Library/NET/Working-with-ZUGFeRD-invoice.md
index 0063b821c6..6f6d7adb27 100644
--- a/Document-Processing/PDF/PDF-Library/NET/Working-with-ZUGFeRD-invoice.md
+++ b/Document-Processing/PDF/PDF-Library/NET/Working-with-ZUGFeRD-invoice.md
@@ -149,10 +149,11 @@ document.Attachments.Add(attachment)
 {% endtabs %}  
 
 N> **XML Naming Guidelines** 
-N> As per the ZUGFeRD standard guidelines, the XML file name must follow the specified format: 
+N> As per the ZUGFeRD / Factur-X standard guidelines, the embedded XML file name must follow the specified format:
 N> 1. **ZUGFeRD 1.0**: The file name should be "ZUGFeRD-invoice.xml". 
 N> 2. **ZUGFeRD 2.0**: The file name should be "zugferd-invoice.xml". 
-N> 3. **Factur-X**: The file name should be "factur-x.xml", except for **XRechnung**, where the file name must be "xrechnung.xml".
+N> 3. **ZUGFeRD 2.1 and later / Factur-X**: The file name should be "factur-x.xml", except for **XRechnung**, where the file name must be "xrechnung.xml".
+N> ZUGFeRD 2.1+ and Factur-X are technically equivalent standards and can be used interchangeably. The term "ZUGFeRD" is commonly used in German-speaking countries, while "Factur-X" is the preferred designation in France and many international contexts.
 
 Using **PDF/A-3b** conformance, you can create a **ZUGFeRD invoice PDF** by specifying the [ZugferdVersion](https://help.syncfusion.com/cr/document-processing/Syncfusion.Pdf.PdfDocument.html#Syncfusion_Pdf_PdfDocument_ZugferdVersion) property as **Factur-X** in the [ZugferdVersion](https://help.syncfusion.com/cr/document-processing/Syncfusion.Pdf.ZugferdVersion.html) Enum.