diff --git a/X10D.Tests/src/BooleanTests.cs b/X10D.Tests/src/Core/BooleanTests.cs
similarity index 85%
rename from X10D.Tests/src/BooleanTests.cs
rename to X10D.Tests/src/Core/BooleanTests.cs
index f571dca..15bad0f 100644
--- a/X10D.Tests/src/BooleanTests.cs
+++ b/X10D.Tests/src/Core/BooleanTests.cs
@@ -1,92 +1,15 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="BooleanExtensions"/>.
+    ///     Tests for <see cref="BooleanExtensions" />.
     /// </summary>
     [TestClass]
     public class BooleanTests
     {
         /// <summary>
-        /// Tests for <see cref="BooleanExtensions.ToByte"/>.
-        /// </summary>
-        [TestMethod]
-        public void ToByte()
-        {
-            const bool a = true;
-            const bool b = false;
-            const byte c = 1;
-            const byte d = 0;
-
-            Assert.IsTrue(a);
-            Assert.IsFalse(b);
-            Assert.AreEqual(c, a.ToByte());
-            Assert.AreEqual(d, b.ToByte());
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.ToInt16"/>.
-        /// </summary>
-        [TestMethod]
-        public void ToInt16()
-        {
-            const bool a = true;
-            const bool b = false;
-
-            Assert.IsTrue(a);
-            Assert.IsFalse(b);
-            Assert.AreEqual(1, a.ToInt16());
-            Assert.AreEqual(0, b.ToInt16());
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.ToInt32"/>.
-        /// </summary>
-        [TestMethod]
-        public void ToInt32()
-        {
-            const bool a = true;
-            const bool b = false;
-
-            Assert.IsTrue(a);
-            Assert.IsFalse(b);
-            Assert.AreEqual(1, a.ToInt32());
-            Assert.AreEqual(0, b.ToInt32());
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.ToInt64"/>.
-        /// </summary>
-        [TestMethod]
-        public void ToInt64()
-        {
-            const bool a = true;
-            const bool b = false;
-
-            Assert.IsTrue(a);
-            Assert.IsFalse(b);
-            Assert.AreEqual(1L, a.ToInt64());
-            Assert.AreEqual(0L, b.ToInt64());
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.Not"/>.
-        /// </summary>
-        [TestMethod]
-        public void Not()
-        {
-            const bool a = true;
-            const bool b = false;
-
-            Assert.IsTrue(a);
-            Assert.IsFalse(b);
-            Assert.IsFalse(a.Not());
-            Assert.IsTrue(b.Not());
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.And"/>.
+        ///     Tests for <see cref="BooleanExtensions.And" />.
         /// </summary>
         [TestMethod]
         public void And()
@@ -107,49 +30,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="BooleanExtensions.Or"/>.
-        /// </summary>
-        [TestMethod]
-        public void Or()
-        {
-            const bool a = true;
-            const bool b = true;
-            const bool c = false;
-            const bool d = false;
-
-            Assert.IsTrue(a);
-            Assert.IsTrue(b);
-            Assert.IsFalse(c);
-            Assert.IsFalse(d);
-
-            Assert.IsTrue(a.Or(b));
-            Assert.IsTrue(b.Or(c));
-            Assert.IsFalse(c.Or(d));
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.XOr"/>.
-        /// </summary>
-        [TestMethod]
-        public void XOr()
-        {
-            const bool a = true;
-            const bool b = true;
-            const bool c = false;
-            const bool d = false;
-
-            Assert.IsTrue(a);
-            Assert.IsTrue(b);
-            Assert.IsFalse(c);
-            Assert.IsFalse(d);
-
-            Assert.IsFalse(a.XOr(b));
-            Assert.IsTrue(b.XOr(c));
-            Assert.IsFalse(c.XOr(d));
-        }
-
-        /// <summary>
-        /// Tests for <see cref="BooleanExtensions.NAnd"/>.
+        ///     Tests for <see cref="BooleanExtensions.NAnd" />.
         /// </summary>
         [TestMethod]
         public void NAnd()
@@ -170,7 +51,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="BooleanExtensions.NOr"/>.
+        ///     Tests for <see cref="BooleanExtensions.NOr" />.
         /// </summary>
         [TestMethod]
         public void NOr()
@@ -191,7 +72,105 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="BooleanExtensions.XNOr"/>.
+        ///     Tests for <see cref="BooleanExtensions.Not" />.
+        /// </summary>
+        [TestMethod]
+        public void Not()
+        {
+            const bool a = true;
+            const bool b = false;
+
+            Assert.IsTrue(a);
+            Assert.IsFalse(b);
+            Assert.IsFalse(a.Not());
+            Assert.IsTrue(b.Not());
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.Or" />.
+        /// </summary>
+        [TestMethod]
+        public void Or()
+        {
+            const bool a = true;
+            const bool b = true;
+            const bool c = false;
+            const bool d = false;
+
+            Assert.IsTrue(a);
+            Assert.IsTrue(b);
+            Assert.IsFalse(c);
+            Assert.IsFalse(d);
+
+            Assert.IsTrue(a.Or(b));
+            Assert.IsTrue(b.Or(c));
+            Assert.IsFalse(c.Or(d));
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.ToByte" />.
+        /// </summary>
+        [TestMethod]
+        public void ToByte()
+        {
+            const bool a = true;
+            const bool b = false;
+            const byte c = 1;
+            const byte d = 0;
+
+            Assert.IsTrue(a);
+            Assert.IsFalse(b);
+            Assert.AreEqual(c, a.ToByte());
+            Assert.AreEqual(d, b.ToByte());
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.ToInt16" />.
+        /// </summary>
+        [TestMethod]
+        public void ToInt16()
+        {
+            const bool a = true;
+            const bool b = false;
+
+            Assert.IsTrue(a);
+            Assert.IsFalse(b);
+            Assert.AreEqual(1, a.ToInt16());
+            Assert.AreEqual(0, b.ToInt16());
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.ToInt32" />.
+        /// </summary>
+        [TestMethod]
+        public void ToInt32()
+        {
+            const bool a = true;
+            const bool b = false;
+
+            Assert.IsTrue(a);
+            Assert.IsFalse(b);
+            Assert.AreEqual(1, a.ToInt32());
+            Assert.AreEqual(0, b.ToInt32());
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.ToInt64" />.
+        /// </summary>
+        [TestMethod]
+        public void ToInt64()
+        {
+            const bool a = true;
+            const bool b = false;
+
+            Assert.IsTrue(a);
+            Assert.IsFalse(b);
+            Assert.AreEqual(1L, a.ToInt64());
+            Assert.AreEqual(0L, b.ToInt64());
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.XNOr" />.
         /// </summary>
         [TestMethod]
         public void XNOr()
@@ -210,5 +189,26 @@ namespace X10D.Tests
             Assert.IsFalse(b.XNOr(c));
             Assert.IsTrue(c.XNOr(d));
         }
+
+        /// <summary>
+        ///     Tests for <see cref="BooleanExtensions.XOr" />.
+        /// </summary>
+        [TestMethod]
+        public void XOr()
+        {
+            const bool a = true;
+            const bool b = true;
+            const bool c = false;
+            const bool d = false;
+
+            Assert.IsTrue(a);
+            Assert.IsTrue(b);
+            Assert.IsFalse(c);
+            Assert.IsFalse(d);
+
+            Assert.IsFalse(a.XOr(b));
+            Assert.IsTrue(b.XOr(c));
+            Assert.IsFalse(c.XOr(d));
+        }
     }
 }
diff --git a/X10D.Tests/src/ByteTests.cs b/X10D.Tests/src/Core/ByteTests.cs
similarity index 76%
rename from X10D.Tests/src/ByteTests.cs
rename to X10D.Tests/src/Core/ByteTests.cs
index 5bf145e..e97061a 100644
--- a/X10D.Tests/src/ByteTests.cs
+++ b/X10D.Tests/src/Core/ByteTests.cs
@@ -1,17 +1,17 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System.Collections.Generic;
     using System.Text;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="ByteExtensions"/>.
+    ///     Tests for <see cref="ByteExtensions" />.
     /// </summary>
     [TestClass]
     public class ByteTests
     {
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.AsString"/>.
+        ///     Tests for <see cref="ByteExtensions.AsString" />.
         /// </summary>
         [TestMethod]
         public void AsString()
@@ -21,7 +21,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetInt16"/>.
+        ///     Tests for <see cref="ByteExtensions.GetInt16" />.
         /// </summary>
         [TestMethod]
         public void GetInt16()
@@ -31,7 +31,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetInt32"/>.
+        ///     Tests for <see cref="ByteExtensions.GetInt32" />.
         /// </summary>
         [TestMethod]
         public void GetInt32()
@@ -41,7 +41,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetInt64"/>.
+        ///     Tests for <see cref="ByteExtensions.GetInt64" />.
         /// </summary>
         [TestMethod]
         public void GetInt64()
@@ -51,7 +51,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetString(IEnumerable{byte})"/>.
+        ///     Tests for <see cref="ByteExtensions.GetString(IEnumerable{byte})" />.
         /// </summary>
         [TestMethod]
         public void GetString()
@@ -61,7 +61,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetString(IEnumerable{byte}, Encoding)"/>.
+        ///     Tests for <see cref="ByteExtensions.GetString(IEnumerable{byte}, Encoding)" />.
         /// </summary>
         [TestMethod]
         public void GetStringAscii()
@@ -71,7 +71,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetUInt16"/>.
+        ///     Tests for <see cref="ByteExtensions.GetUInt16" />.
         /// </summary>
         [TestMethod]
         public void GetUInt16()
@@ -81,7 +81,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetUInt32"/>.
+        ///     Tests for <see cref="ByteExtensions.GetUInt32" />.
         /// </summary>
         [TestMethod]
         public void GetUInt32()
@@ -91,7 +91,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ByteExtensions.GetUInt64"/>.
+        ///     Tests for <see cref="ByteExtensions.GetUInt64" />.
         /// </summary>
         [TestMethod]
         public void GetUInt64()
diff --git a/X10D.Tests/src/CharTests.cs b/X10D.Tests/src/Core/CharTests.cs
similarity index 78%
rename from X10D.Tests/src/CharTests.cs
rename to X10D.Tests/src/Core/CharTests.cs
index c0f328d..d462d59 100644
--- a/X10D.Tests/src/CharTests.cs
+++ b/X10D.Tests/src/Core/CharTests.cs
@@ -1,17 +1,17 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using System.Linq;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="CharExtensions"/>.
+    ///     Tests for <see cref="CharExtensions" />.
     /// </summary>
     [TestClass]
     public class CharTests
     {
         /// <summary>
-        /// Tests for <see cref="CharExtensions.Repeat"/>.
+        ///     Tests for <see cref="CharExtensions.Repeat" />.
         /// </summary>
         [TestMethod]
         public void Random()
@@ -24,7 +24,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="CharExtensions.Repeat"/>.
+        ///     Tests for <see cref="CharExtensions.Repeat" />.
         /// </summary>
         [TestMethod]
         public void Repeat()
diff --git a/X10D.Tests/src/ComparableTests.cs b/X10D.Tests/src/Core/ComparableTests.cs
similarity index 72%
rename from X10D.Tests/src/ComparableTests.cs
rename to X10D.Tests/src/Core/ComparableTests.cs
index 7d27db9..c477f9d 100644
--- a/X10D.Tests/src/ComparableTests.cs
+++ b/X10D.Tests/src/Core/ComparableTests.cs
@@ -1,15 +1,15 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="ComparableExtensions"/>.
+    ///     Tests for <see cref="ComparableExtensions" />.
     /// </summary>
     [TestClass]
     public class ComparableTests
     {
         /// <summary>
-        /// Tests for <see cref="ComparableExtensions.Between{T}"/>.
+        ///     Tests for <see cref="ComparableExtensions.Between{T}" />.
         /// </summary>
         [TestMethod]
         public void Between()
diff --git a/X10D.Tests/src/ConvertibleTests.cs b/X10D.Tests/src/Core/ConvertibleTests.cs
similarity index 72%
rename from X10D.Tests/src/ConvertibleTests.cs
rename to X10D.Tests/src/Core/ConvertibleTests.cs
index c366aea..cc11fc2 100644
--- a/X10D.Tests/src/ConvertibleTests.cs
+++ b/X10D.Tests/src/Core/ConvertibleTests.cs
@@ -1,16 +1,16 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="ConvertibleExtensions"/>.
+    ///     Tests for <see cref="ConvertibleExtensions" />.
     /// </summary>
     [TestClass]
     public class ConvertibleTests
     {
         /// <summary>
-        /// Tests for <see cref="ConvertibleExtensions.To{T}"/>.
+        ///     Tests for <see cref="ConvertibleExtensions.To{T}" />.
         /// </summary>
         [TestMethod]
         public void To()
@@ -21,7 +21,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ConvertibleExtensions.ToOrDefault{T}(System.IConvertible, System.IFormatProvider)"/>.
+        ///     Tests for <see cref="ConvertibleExtensions.ToOrDefault{T}(System.IConvertible, System.IFormatProvider)" />.
         /// </summary>
         [TestMethod]
         public void ToOrDefault()
@@ -35,7 +35,17 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="ConvertibleExtensions.ToOrOther{T}(System.IConvertible, T, System.IFormatProvider)"/>.
+        ///     Tests for <see cref="ConvertibleExtensions.ToOrNull{T}(System.IConvertible, System.IFormatProvider)" />.
+        /// </summary>
+        [TestMethod]
+        public void ToOrNull()
+        {
+            Assert.IsFalse("foo".ToOrNull(out ConvertibleTests t));
+            Assert.IsNull(t);
+        }
+
+        /// <summary>
+        ///     Tests for <see cref="ConvertibleExtensions.ToOrOther{T}(System.IConvertible, T, System.IFormatProvider)" />.
         /// </summary>
         [TestMethod]
         public void ToOrOther()
@@ -44,15 +54,5 @@ namespace X10D.Tests
             Assert.IsFalse("Foo".ToOrOther(out var d, 2.0));
             Assert.AreEqual(2.0, d);
         }
-
-        /// <summary>
-        /// Tests for <see cref="ConvertibleExtensions.ToOrNull{T}(System.IConvertible, System.IFormatProvider)"/>.
-        /// </summary>
-        [TestMethod]
-        public void ToOrNull()
-        {
-            Assert.IsFalse("foo".ToOrNull(out ConvertibleTests t));
-            Assert.IsNull(t);
-        }
     }
 }
diff --git a/X10D.Tests/src/DateTimeTests.cs b/X10D.Tests/src/Core/DateTimeTests.cs
similarity index 76%
rename from X10D.Tests/src/DateTimeTests.cs
rename to X10D.Tests/src/Core/DateTimeTests.cs
index c7b6502..a670af9 100644
--- a/X10D.Tests/src/DateTimeTests.cs
+++ b/X10D.Tests/src/Core/DateTimeTests.cs
@@ -1,30 +1,30 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="DateTimeExtensions"/>.
+    ///     Tests for <see cref="DateTimeExtensions" />.
     /// </summary>
     [TestClass]
     public class DateTimeTests
     {
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.Age(DateTime)"/>.
+        ///     Tests for <see cref="DateTimeExtensions.Age(DateTime)" />.
         /// </summary>
         [TestMethod]
         public void Age()
         {
             // no choice but to create dynamic based on today's date.
             // age varies with time
-            DateTime now = DateTime.Now;
+            var now = DateTime.Now;
             var dt = new DateTime(now.Year - 18, 1, 1);
 
             Assert.AreEqual(18, dt.Age());
         }
 
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.First"/>.
+        ///     Tests for <see cref="DateTimeExtensions.First" />.
         /// </summary>
         [TestMethod]
         public void First()
@@ -35,13 +35,13 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.FirstDayOfMonth"/>.
+        ///     Tests for <see cref="DateTimeExtensions.FirstDayOfMonth" />.
         /// </summary>
         [TestMethod]
         public void FirstDayOfMonth()
         {
             var dt = new DateTime(2018, 6, 20);
-            DateTime first = dt.FirstDayOfMonth();
+            var first = dt.FirstDayOfMonth();
 
             Assert.AreEqual(dt.Year, first.Year);
             Assert.AreEqual(dt.Month, first.Month);
@@ -49,14 +49,14 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.Last"/>.
+        ///     Tests for <see cref="DateTimeExtensions.Last" />.
         /// </summary>
         [TestMethod]
         public void Last()
         {
             {
                 var dt = new DateTime(2019, 12, 1);
-                DateTime last = dt.Last(DayOfWeek.Wednesday);
+                var last = dt.Last(DayOfWeek.Wednesday);
 
                 Assert.AreEqual(dt.Year, last.Year);
                 Assert.AreEqual(dt.Month, last.Month);
@@ -65,7 +65,7 @@ namespace X10D.Tests
 
             {
                 var dt = new DateTime(2020, 4, 14);
-                DateTime last = dt.Last(DayOfWeek.Friday);
+                var last = dt.Last(DayOfWeek.Friday);
 
                 Assert.AreEqual(dt.Year, last.Year);
                 Assert.AreEqual(dt.Month, last.Month);
@@ -79,13 +79,13 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.LastDayOfMonth"/>.
+        ///     Tests for <see cref="DateTimeExtensions.LastDayOfMonth" />.
         /// </summary>
         [TestMethod]
         public void LastDayOfMonth()
         {
             var dt = new DateTime(2016, 2, 4);
-            DateTime last = dt.LastDayOfMonth();
+            var last = dt.LastDayOfMonth();
 
             Assert.AreEqual(dt.Year, last.Year);
             Assert.AreEqual(dt.Month, last.Month);
@@ -93,7 +93,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DateTimeExtensions.ToUnixTimeStamp"/>.
+        ///     Tests for <see cref="DateTimeExtensions.ToUnixTimeStamp" />.
         /// </summary>
         [TestMethod]
         public void ToUnixTimestamp()
diff --git a/X10D.Tests/src/DictionaryTests.cs b/X10D.Tests/src/Core/DictionaryTests.cs
similarity index 78%
rename from X10D.Tests/src/DictionaryTests.cs
rename to X10D.Tests/src/Core/DictionaryTests.cs
index e85b895..983fc9b 100644
--- a/X10D.Tests/src/DictionaryTests.cs
+++ b/X10D.Tests/src/Core/DictionaryTests.cs
@@ -1,16 +1,16 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System.Collections.Generic;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="DictionaryExtensions"/>.
+    ///     Tests for <see cref="DictionaryExtensions" />.
     /// </summary>
     [TestClass]
     public class DictionaryTests
     {
         /// <summary>
-        /// Tests for <see cref="DictionaryExtensions.ToConnectionString{T1,T2}(IDictionary{T1,T2})"/>.
+        ///     Tests for <see cref="DictionaryExtensions.ToConnectionString{T1,T2}(IDictionary{T1,T2})" />.
         /// </summary>
         [TestMethod]
         public void ToConnectionString()
@@ -25,7 +25,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DictionaryExtensions.ToGetParameters{T1,T2}(IDictionary{T1,T2})"/>.
+        ///     Tests for <see cref="DictionaryExtensions.ToGetParameters{T1,T2}(IDictionary{T1,T2})" />.
         /// </summary>
         [TestMethod]
         public void ToGetParameters()
diff --git a/X10D.Tests/src/DoubleTests.cs b/X10D.Tests/src/Core/DoubleTests.cs
similarity index 76%
rename from X10D.Tests/src/DoubleTests.cs
rename to X10D.Tests/src/Core/DoubleTests.cs
index 9f7a25a..9990370 100644
--- a/X10D.Tests/src/DoubleTests.cs
+++ b/X10D.Tests/src/Core/DoubleTests.cs
@@ -1,16 +1,16 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="DoubleExtensions"/>.
+    ///     Tests for <see cref="DoubleExtensions" />.
     /// </summary>
     [TestClass]
     public class DoubleTests
     {
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.Clamp"/>.
+        ///     Tests for <see cref="DoubleExtensions.Clamp" />.
         /// </summary>
         [TestMethod]
         public void Clamp()
@@ -20,7 +20,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.DegreesToRadians"/>.
+        ///     Tests for <see cref="DoubleExtensions.DegreesToRadians" />.
         /// </summary>
         [TestMethod]
         public void DegreesToRadians()
@@ -30,7 +30,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.GetBytes"/>.
+        ///     Tests for <see cref="DoubleExtensions.GetBytes" />.
         /// </summary>
         [TestMethod]
         public void GetBytes()
@@ -41,7 +41,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.IsEven"/>.
+        ///     Tests for <see cref="DoubleExtensions.IsEven" />.
         /// </summary>
         [TestMethod]
         public void IsEven()
@@ -51,7 +51,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.IsOdd"/>.
+        ///     Tests for <see cref="DoubleExtensions.IsOdd" />.
         /// </summary>
         [TestMethod]
         public void IsOdd()
@@ -61,7 +61,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.RadiansToDegrees"/>.
+        ///     Tests for <see cref="DoubleExtensions.RadiansToDegrees" />.
         /// </summary>
         [TestMethod]
         public void RadiansToDegrees()
@@ -71,7 +71,7 @@ namespace X10D.Tests
         }
 
         /// <summary>
-        /// Tests for <see cref="DoubleExtensions.Round"/>.
+        ///     Tests for <see cref="DoubleExtensions.Round" />.
         /// </summary>
         [TestMethod]
         public void Round()
diff --git a/X10D.Tests/src/EnumerableTests.cs b/X10D.Tests/src/Core/EnumerableTests.cs
similarity index 87%
rename from X10D.Tests/src/EnumerableTests.cs
rename to X10D.Tests/src/Core/EnumerableTests.cs
index c87ef8a..6da9ac3 100644
--- a/X10D.Tests/src/EnumerableTests.cs
+++ b/X10D.Tests/src/Core/EnumerableTests.cs
@@ -1,17 +1,17 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System.Collections.Generic;
     using System.Linq;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="EnumerableExtensions"/>.
+    ///     Tests for <see cref="EnumerableExtensions" />.
     /// </summary>
     [TestClass]
     public class EnumerableTests
     {
         /// <summary>
-        /// Tests for <see cref="EnumerableExtensions.Split{T}"/> using an array of <see cref="byte"/>.
+        ///     Tests for <see cref="EnumerableExtensions.Split{T}" /> using an array of <see cref="byte" />.
         /// </summary>
         [TestMethod]
         public void SplitByte()
@@ -32,7 +32,7 @@
         }
 
         /// <summary>
-        /// Tests for <see cref="EnumerableExtensions.Split{T}"/> using an array of <see cref="int"/>.
+        ///     Tests for <see cref="EnumerableExtensions.Split{T}" /> using an array of <see cref="int" />.
         /// </summary>
         [TestMethod]
         public void SplitInt32()
diff --git a/X10D.Tests/src/ReflectionTests.cs b/X10D.Tests/src/Core/ReflectionTests.cs
similarity index 80%
rename from X10D.Tests/src/ReflectionTests.cs
rename to X10D.Tests/src/Core/ReflectionTests.cs
index da95110..b182a4b 100644
--- a/X10D.Tests/src/ReflectionTests.cs
+++ b/X10D.Tests/src/Core/ReflectionTests.cs
@@ -1,17 +1,17 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using System.ComponentModel;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="ReflectionExtensions"/>.
+    ///     Tests for <see cref="ReflectionExtensions" />.
     /// </summary>
     [TestClass]
     public class ReflectionTests
     {
         /// <summary>
-        /// Test for <see cref="ReflectionExtensions.GetDefaultValue{T}(System.Reflection.MemberInfo)"/>.
+        ///     Test for <see cref="ReflectionExtensions.GetDefaultValue{T}(System.Reflection.MemberInfo)" />.
         /// </summary>
         [TestMethod]
         public void GetDefaultValue()
@@ -25,7 +25,7 @@
         }
 
         /// <summary>
-        /// Test for <see cref="ReflectionExtensions.GetDescription(System.Reflection.MemberInfo)"/>.
+        ///     Test for <see cref="ReflectionExtensions.GetDescription(System.Reflection.MemberInfo)" />.
         /// </summary>
         [TestMethod]
         public void GetDescription()
@@ -39,7 +39,7 @@
         }
 
         /// <summary>
-        /// Test for <see cref="ReflectionExtensions.GetDescription(System.Reflection.MemberInfo)"/>.
+        ///     Test for <see cref="ReflectionExtensions.GetDescription(System.Reflection.MemberInfo)" />.
         /// </summary>
         [TestMethod]
         public void SelectFromCustomAttribute()
diff --git a/X10D.Tests/src/StringTests.cs b/X10D.Tests/src/Core/StringTests.cs
similarity index 77%
rename from X10D.Tests/src/StringTests.cs
rename to X10D.Tests/src/Core/StringTests.cs
index b4ccf4f..32d6fb4 100644
--- a/X10D.Tests/src/StringTests.cs
+++ b/X10D.Tests/src/Core/StringTests.cs
@@ -1,16 +1,16 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System.Linq;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="StringExtensions"/>.
+    ///     Tests for <see cref="StringExtensions" />.
     /// </summary>
     [TestClass]
     public class StringTests
     {
         /// <summary>
-        /// Tests for <see cref="StringExtensions.Repeat"/>.
+        ///     Tests for <see cref="StringExtensions.Repeat" />.
         /// </summary>
         [TestMethod]
         public void Repeat()
@@ -19,7 +19,7 @@
         }
 
         /// <summary>
-        /// Tests for <see cref="StringExtensions.Split"/>.
+        ///     Tests for <see cref="StringExtensions.Split" />.
         /// </summary>
         [TestMethod]
         public void Split()
diff --git a/X10D.Tests/src/TimeSpanParserTests.cs b/X10D.Tests/src/Core/TimeSpanParserTests.cs
similarity index 83%
rename from X10D.Tests/src/TimeSpanParserTests.cs
rename to X10D.Tests/src/Core/TimeSpanParserTests.cs
index a952280..bbbb5e7 100644
--- a/X10D.Tests/src/TimeSpanParserTests.cs
+++ b/X10D.Tests/src/Core/TimeSpanParserTests.cs
@@ -1,16 +1,16 @@
-namespace X10D.Tests
+namespace X10D.Tests.Core
 {
     using System;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
 
     /// <summary>
-    /// Tests for <see cref="TimeSpanParser"/>.
+    ///     Tests for <see cref="TimeSpanParser" />.
     /// </summary>
     [TestClass]
     public class TimeSpanParserTests
     {
         /// <summary>
-        /// Tests for <see cref="TimeSpanParser.Parse"/>.
+        ///     Tests for <see cref="TimeSpanParser.Parse" />.
         /// </summary>
         [TestMethod]
         public void TestParser()