diff --git a/MCTG/DataPersistence/DataContractJSON.cs b/MCTG/DataPersistence/DataContractJSON.cs
index 382a4eb..05db57e 100644
--- a/MCTG/DataPersistence/DataContractJSON.cs
+++ b/MCTG/DataPersistence/DataContractJSON.cs
@@ -34,7 +34,12 @@ namespace DataPersistence
             if (dataContractJsonSerializerSettings is null)
                 _dataContractJsonSerializerSettings = new DataContractJsonSerializerSettings()
                 {
-                    KnownTypes = new[] { typeof(Recipe) }
+                    KnownTypes = new[]
+                    {
+                        typeof(Recipe),
+                        typeof(Review),
+                        typeof(User)
+                    }
                 };
             else
                 _dataContractJsonSerializerSettings = dataContractJsonSerializerSettings;
diff --git a/MCTG/DataPersistence/DataContractXML.cs b/MCTG/DataPersistence/DataContractXML.cs
index 3944c85..92f4baf 100644
--- a/MCTG/DataPersistence/DataContractXML.cs
+++ b/MCTG/DataPersistence/DataContractXML.cs
@@ -42,7 +42,12 @@ namespace DataPersistence
             if (dataContractSerializerSettings is null)
                 _dataContractSerializerSettings = new DataContractSerializerSettings()
                 {
-                    KnownTypes = new Type[] { typeof(Recipe) },
+                    KnownTypes = new Type[]
+                    {
+                        typeof(Recipe),
+                        typeof(Review),
+                        typeof(User)
+                    },
                     PreserveObjectReferences = true
                 };
             else
diff --git a/MCTG/Model/Recipes/Recipe.cs b/MCTG/Model/Recipes/Recipe.cs
index de29cfc..b7ced0d 100644
--- a/MCTG/Model/Recipes/Recipe.cs
+++ b/MCTG/Model/Recipes/Recipe.cs
@@ -25,6 +25,9 @@ namespace Model
         [DataMember(Name = "id")]
         public int Id { get; init; }
 
+        /// <summary>
+        /// List of reviews of this recipe.
+        /// </summary>
         [DataMember(Name = "reviews")]
         public List<Review> Reviews { get; private set; }
 
@@ -94,12 +97,31 @@ namespace Model
             : this(title, null, new List<Review>(), preparationSteps)
         {
         }
+
+        /// <summary>
+        /// <inheritdoc cref="Recipe.Recipe(string, int?, List{Review}, PreparationStep[])"/>
+        /// </summary>
+        /// <param name="title">The title of the recipe.</param>
+        /// <param name="id">The id of the recipe. If not given, get a new id.</param>
+        /// <param name="preparationSteps">The steps of the preparation of the meal.</param>
+        public Recipe(string title, int? id, params PreparationStep[] preparationSteps)
+            : this(title, id, new List<Review>(), preparationSteps)
+        {
+        }
         #endregion
 
         #region Methods
+        /// <summary>
+        /// Add a review for the recipe.
+        /// </summary>
+        /// <param name="review">The new review to add.</param>
         public void AddReview(Review review)
             => Reviews.Add(review);
 
+        /// <summary>
+        /// Get a string representing all the reviews and their informations.
+        /// </summary>
+        /// <returns></returns>
         public string GetReviews()
         {
             StringBuilder sb = new StringBuilder("Reviews:\n------------------------------\n");
diff --git a/MCTG/Model/Recipes/Review.cs b/MCTG/Model/Recipes/Review.cs
index bd0a988..caf19cc 100644
--- a/MCTG/Model/Recipes/Review.cs
+++ b/MCTG/Model/Recipes/Review.cs
@@ -1,19 +1,27 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Runtime.Serialization;
 using System.Security.Cryptography;
 using System.Text;
 using System.Threading.Tasks;
+using System.Xml.Linq;
 
 namespace Model
 {
+    [DataContract(Name = "review")]
     public class Review : IEquatable<Review>
     {
+        [DataMember(Name = "stars")]
         private int _stars;
+
+        [DataMember(Name = "content")]
         private string _content = "";
 
+        [DataMember(Name = "id")]
         public int Id { get; init; }
 
+        [DataMember(Name = "author")]
         public User Author { get; private set; }
 
         public int Stars