diff --git a/OpenTrans.net/BuyerProductId.cs b/OpenTrans.net/BuyerProductId.cs
index 55dba14..bf7415e 100644
--- a/OpenTrans.net/BuyerProductId.cs
+++ b/OpenTrans.net/BuyerProductId.cs
@@ -21,9 +21,16 @@ namespace OpenTrans.net
     /// <summary>
     /// Identifier of the product from the perspective of the buyer. The included elements ensure the capability of a unique identification of a product.
     /// </summary>
-    public class BuyerProductId
+    public class BuyerProductId    
     {
+        /// <summary>
+        /// The actual Id that is assigned from the perspective of the buyer
+        /// </summary>
         public string Id { get; set; }
+
+        /// <summary>
+        /// This attribute specifies the type of ID, i.e. indicates the organization that has issued the ID.
+        /// </summary>
         public BuyerProductIdTypes Type { get; set; }
     }
 }
diff --git a/OpenTrans.net/BuyerProductIdTypes.cs b/OpenTrans.net/BuyerProductIdTypes.cs
index 8b759c8..055d86d 100644
--- a/OpenTrans.net/BuyerProductIdTypes.cs
+++ b/OpenTrans.net/BuyerProductIdTypes.cs
@@ -18,6 +18,9 @@
  */
 namespace OpenTrans.net
 {
+    /// <summary>
+    /// Types for the product number used by the buying company.
+    /// </summary>
     public enum BuyerProductIdTypes
     {
         /// <summary> Artikelnummer des einkaufenden Unternehmens </summary>
diff --git a/OpenTrans.net/OpenTrans.net.csproj b/OpenTrans.net/OpenTrans.net.csproj
index f78a215..d89ccc7 100644
--- a/OpenTrans.net/OpenTrans.net.csproj
+++ b/OpenTrans.net/OpenTrans.net.csproj
@@ -4,8 +4,8 @@
     <TargetFramework>netstandard2.0</TargetFramework>
     <PackageLicenseExpression>http://www.apache.org/licenses/LICENSE-2.0</PackageLicenseExpression>
     <Authors>Stephan Stapel, stephan@s2-industries.com</Authors>
-    <Version>4.0.1</Version>
-    <AssemblyVersion>4.0.1.0</AssemblyVersion>
+    <Version>4.0.2</Version>
+    <AssemblyVersion>4.0.2.0</AssemblyVersion>
     <FileVersion>4.0.1.0</FileVersion>
   </PropertyGroup>
 
diff --git a/OpenTrans.net/Order.cs b/OpenTrans.net/Order.cs
index 3adb0c7..7873aa2 100644
--- a/OpenTrans.net/Order.cs
+++ b/OpenTrans.net/Order.cs
@@ -25,20 +25,86 @@
 
 namespace OpenTrans.net
 {
+    /// <summary>
+    /// Order that is issues from a Buyer to a Seller.
+    /// </summary>
     public class Order
     {
+        /// <summary>
+        /// Unique order number of the buyer
+        /// </summary>
         public string Id { get; set; }
+
+        /// <summary>
+        /// Date of the order
+        /// </summary>
         public DateTime? OrderDate { get; set; }
+
+        /// <summary>
+        /// Date of shipment. The delivery date specifies the date the commissioned goods are accepted
+        /// by the buyer.If the delivery date deviates from the one specified in the header, the
+        /// delivery date on item level is valid.To specify exact one date for the shipment, e.g. in the
+        /// RECEIPTACKNOWLEDGEMENT-document.
+        /// 
+        /// This property is accompanied by the property DesiredDeliveryDateEnd which specifies the end of the 
+        /// delivery window.
+        /// </summary>
         public DateTime DesiredDeliveryDateStart { get; set; }
+
+        /// <summary>
+        /// Date of shipment. The delivery date specifies the date the commissioned goods are accepted
+        /// by the buyer.If the delivery date deviates from the one specified in the header, the
+        /// delivery date on item level is valid.To specify exact one date for the shipment, e.g. in the
+        /// RECEIPTACKNOWLEDGEMENT-document.
+        /// 
+        /// This property is accompanied by the property DesiredDeliveryDateStart which specifies the start of the 
+        /// delivery window.
+        /// </summary>
         public DateTime DesiredDeliveryDateEnd { get; set; }
+
+        /// <summary>
+        /// The element is related to an item and refers to the previous order where the item was ordered
+        /// by the customer(purchasing party)
+        /// </summary>
         public CustomerOrderReference CustomerOrderReference { get; set; }
+
+        /// <summary>
+        /// Reference to the business partners integrated in the process of the document flow
+        /// </summary>
         public OrderPartiesReference OrderPartiesReference { get; set; }
+
+        /// <summary>
+        /// Provides the currency that is default for all price information in the catalog. If the price of a
+        /// product has a different currency, or this element is not used, the the currency has to be
+        /// specified in the corresponding element for the respective product.
+        /// </summary>
         public string Currency { get; set; }
+
+        /// <summary>
+        /// Flag to indicate whether partial shipment is allowed. If allowed the value is TRUE, FALSE
+        /// otherwise.The flag is binding for the order, i.e. if the value is set to FALSE and only partial
+        ///  shipments can be made by the recipient of the order, the order shall be invalid.
+        /// </summary>
         public bool PartialShipmentAllowed { get; set; }
+
+        /// <summary>
+        /// List of parties that are relevant to this business document
+        /// </summary>
         public List<Party> Parties { get; set; } = new List<Party>();
         public List<OrderItem> OrderItems { get; set; } = new List<OrderItem>();
         public OrderSummary OrderSummary { get; set; }
 
+
+        /// <summary>
+        /// Loads an order from the given stream.
+        /// 
+        /// Make sure that the stream is open. After successful reading, the stream is left open, i.e.
+        /// the caller of the library has to take care of the stream lifecycle.
+        /// 
+        /// If the stream is not open or readable, an IllegalStreamException exception is raised.
+        /// </summary>
+        /// <param name="stream"></param>
+        /// <returns></returns>
         public static Order Load(Stream stream)
         {
             OrderReader reader = new OrderReader();
@@ -46,6 +112,12 @@ public static Order Load(Stream stream)
         } // !Load()
 
 
+        /// <summary>
+        /// Loads an order from the given file.
+        /// If the file does not exist, a FileNotFoundException exception is raised.
+        /// </summary>
+        /// <param name="filename"></param>
+        /// <returns></returns>
         public static Order Load(string filename)
         {
             OrderReader reader = new OrderReader();
@@ -67,6 +139,10 @@ public void Save(Stream stream)
         } // !Save()
 
 
+        /// <summary>
+        /// Saves the order into the given file.
+        /// </summary>
+        /// <param name="filename"></param>
         public void Save(string filename)
         {
             OrderWriter writer = new OrderWriter();
diff --git a/OpenTrans.net/OrderResponse.cs b/OpenTrans.net/OrderResponse.cs
index 1f48c32..5df9747 100644
--- a/OpenTrans.net/OrderResponse.cs
+++ b/OpenTrans.net/OrderResponse.cs
@@ -36,6 +36,16 @@ public class OrderResponse
 
 
 
+        /// <summary>
+        /// Loads an order response from the given stream.
+        /// 
+        /// Make sure that the stream is open. After successful reading, the stream is left open, i.e.
+        /// the caller of the library has to take care of the stream lifecycle.
+        /// 
+        /// If the stream is not open or readable, an IllegalStreamException exception is raised.
+        /// </summary>
+        /// <param name="stream"></param>
+        /// <returns></returns>
         public static OrderResponse Load(Stream stream)
         {
             OrderResponseReader reader = new OrderResponseReader();
@@ -43,6 +53,12 @@ public static OrderResponse Load(Stream stream)
         } // !Load()
 
 
+        /// <summary>
+        /// Loads an order response from the given file.
+        /// If the file does not exist, a FileNotFoundException exception is raised.
+        /// </summary>
+        /// <param name="filename"></param>
+        /// <returns></returns>
         public static OrderResponse Load(string filename)
         {
             OrderResponseReader reader = new OrderResponseReader();
@@ -64,6 +80,10 @@ public void Save(Stream stream)
         } // !Save()
 
 
+        /// <summary>
+        /// Saves the order response into the given file.
+        /// </summary>
+        /// <param name="filename"></param>
         public void Save(string filename)
         {
             OrderResponseWriter writer = new OrderResponseWriter();