diff --git a/Distribution/xDGA Sample.xlsx b/Distribution/xDGA Sample.xlsx
index b89b022..b750554 100644
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diff --git a/Distribution/xDGA.ADDIN.xll b/Distribution/xDGA.ADDIN.xll
index 6d03d39..e42033c 100644
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diff --git a/Distribution/xDGA.ADDIN64.xll b/Distribution/xDGA.ADDIN64.xll
index 892620a..3572c3f 100644
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diff --git a/Distribution/xDGA32.zip b/Distribution/xDGA32.zip
new file mode 100644
index 0000000..5cea22e
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diff --git a/Distribution/xDGA64.zip b/Distribution/xDGA64.zip
new file mode 100644
index 0000000..d117ac2
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diff --git a/VERSIONS.md b/VERSIONS.md
index 24515b4..582e3a2 100644
--- a/VERSIONS.md
+++ b/VERSIONS.md
@@ -1,5 +1,12 @@
 # xDGA
 
+## Version 0.6
+### October 2017
+
+#### xDGA.CORE
+* Corrected Duval Pentagons areas. Thanks to Nick and Ania from work who
+  pointed out the issue and suggested a solution.
+
 ## Version 0.5
 ### August 2017
 
diff --git a/xDGA.CORE/Algorithms/DuvalPentagons/AbstractDuvalPentagonRule.cs b/xDGA.CORE/Algorithms/DuvalPentagons/AbstractDuvalPentagonRule.cs
index a018576..e339ec9 100644
--- a/xDGA.CORE/Algorithms/DuvalPentagons/AbstractDuvalPentagonRule.cs
+++ b/xDGA.CORE/Algorithms/DuvalPentagons/AbstractDuvalPentagonRule.cs
@@ -20,7 +20,6 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using xDGA.CORE.Interfaces;
diff --git a/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonOneRule.cs b/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonOneRule.cs
index d5950e2..d2d97ff 100644
--- a/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonOneRule.cs
+++ b/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonOneRule.cs
@@ -44,7 +44,7 @@ public DuvalPentagonOneRule() : base("Duval Pentagon 1", Gas.Hydrogen, Gas.Ethan
                 Coordinates =
                 {
                     new CartesianCoordinate(0.0, 40.0),
-                    new CartesianCoordinate(38.0, 12.0),
+                    new CartesianCoordinate(38.0, 12.4),
                     new CartesianCoordinate(32.0, -6.0),
                     new CartesianCoordinate(4.0, 16.0),
                     new CartesianCoordinate(0.0, 1.5)
@@ -67,9 +67,10 @@ public DuvalPentagonOneRule() : base("Duval Pentagon 1", Gas.Hydrogen, Gas.Ethan
                 Coordinates =
                 {
                     new CartesianCoordinate(24.0, -30.0),
-                    new CartesianCoordinate(1.0, -32.0),
+                    new CartesianCoordinate(1.0, -32.4),
+                    new CartesianCoordinate(-23.3, -32.4),
                     new CartesianCoordinate(-6.0, -4.0),
-                    new CartesianCoordinate(-1.0, -2.0)   
+                    new CartesianCoordinate(-1.0, -2.0)
                 }
             });
 
@@ -77,8 +78,8 @@ public DuvalPentagonOneRule() : base("Duval Pentagon 1", Gas.Hydrogen, Gas.Ethan
             {
                 Coordinates =
                 {
-                    new CartesianCoordinate(1.0, -32.0),
-                    new CartesianCoordinate(-22.5, -32.0),
+                    new CartesianCoordinate(1.0, -32.4),
+                    new CartesianCoordinate(-22.5, -32.4),
                     new CartesianCoordinate(-6.0, -4.0)
                 }
             });
@@ -89,9 +90,10 @@ public DuvalPentagonOneRule() : base("Duval Pentagon 1", Gas.Hydrogen, Gas.Ethan
                 {
                     new CartesianCoordinate(0.0, 1.5),
                     new CartesianCoordinate(-35.0, 3.0),
-                    new CartesianCoordinate(-22.5, -32.0),
+                    new CartesianCoordinate(-22.5, -32.4),
                     new CartesianCoordinate(-6.0, -4.0),
-                    new CartesianCoordinate(-1.0, -2.0)
+                    new CartesianCoordinate(-1.0, -2.0),
+                    new CartesianCoordinate(-23.3, -32.4)
                 }
             });
 
@@ -105,7 +107,8 @@ public DuvalPentagonOneRule() : base("Duval Pentagon 1", Gas.Hydrogen, Gas.Ethan
                     new CartesianCoordinate(-1.0, 24.5),
                     new CartesianCoordinate(-1.0, 33.0),
                     new CartesianCoordinate(0.0, 33.0),
-                    new CartesianCoordinate(0.0, 40.0)
+                    new CartesianCoordinate(0.0, 40.0),
+                    new CartesianCoordinate(-38.0, -12.4)
                 }
             });
         }
diff --git a/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonTwoRule.cs b/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonTwoRule.cs
index d549d2b..13f9e39 100644
--- a/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonTwoRule.cs
+++ b/xDGA.CORE/Algorithms/DuvalPentagons/DuvalPentagonTwoRule.cs
@@ -44,7 +44,7 @@ public DuvalPentagonTwoRule() : base("Duval Pentagon 2", Gas.Hydrogen, Gas.Ethan
                 Coordinates =
                 {
                     new CartesianCoordinate(0.0, 40.0),
-                    new CartesianCoordinate(38.0, 12.0),
+                    new CartesianCoordinate(38.0, 12.4),
                     new CartesianCoordinate(32.0, -6.0),
                     new CartesianCoordinate(4.0, 16.0),
                     new CartesianCoordinate(0.0, 1.5)
@@ -72,7 +72,8 @@ public DuvalPentagonTwoRule() : base("Duval Pentagon 2", Gas.Hydrogen, Gas.Ethan
                     new CartesianCoordinate(-1.0, 24.5),
                     new CartesianCoordinate(-1.0, 33.0),
                     new CartesianCoordinate(0.0, 33.0),
-                    new CartesianCoordinate(0.0, 40.0)
+                    new CartesianCoordinate(0.0, 40.0),
+                    new CartesianCoordinate(-38.0, -12.4)
                 }
             });
 
@@ -82,7 +83,9 @@ public DuvalPentagonTwoRule() : base("Duval Pentagon 2", Gas.Hydrogen, Gas.Ethan
                 {
                     new CartesianCoordinate(24.0, -30.0),
                     new CartesianCoordinate(-3.5, -3.0),
-                    new CartesianCoordinate(2.5, -32.0)
+                    new CartesianCoordinate(-1.0, -2.0),
+                    new CartesianCoordinate(2.5, -32.4),
+                    new CartesianCoordinate(23.3, -32.4)
                 }
             });
 
@@ -90,10 +93,10 @@ public DuvalPentagonTwoRule() : base("Duval Pentagon 2", Gas.Hydrogen, Gas.Ethan
             {
                 Coordinates =
                 {
-                    new CartesianCoordinate(2.5, -32.0),
+                    new CartesianCoordinate(2.5, -32.4),
                     new CartesianCoordinate(-3.5, -3.0),
                     new CartesianCoordinate(-11.0, -8.0),
-                    new CartesianCoordinate(-21.5, -32.0)
+                    new CartesianCoordinate(-21.5, -32.4)
                 }
             });
 
@@ -101,12 +104,13 @@ public DuvalPentagonTwoRule() : base("Duval Pentagon 2", Gas.Hydrogen, Gas.Ethan
             {
                 Coordinates =
                 {
-                    new CartesianCoordinate(-21.5, -32.0),
+                    new CartesianCoordinate(-21.5, -32.4),
                     new CartesianCoordinate(-11.0, -8.0),
                     new CartesianCoordinate(-3.5, -3.0),
                     new CartesianCoordinate(-1.0, -2.0),
                     new CartesianCoordinate(0.0, 1.5),
-                    new CartesianCoordinate(-35.0, 3.0)
+                    new CartesianCoordinate(-35.0, 3.0),
+                    new CartesianCoordinate(-23.3, -32.4)
                 }
             });
         }
diff --git a/xDGA.CORE/Models/Area.cs b/xDGA.CORE/Models/Area.cs
index 0306f47..aa35b8c 100644
--- a/xDGA.CORE/Models/Area.cs
+++ b/xDGA.CORE/Models/Area.cs
@@ -21,6 +21,7 @@
 // SOFTWARE.
 
 using System;
+using System.Linq;
 using System.Collections.Generic;
 
 namespace xDGA.CORE.Models
@@ -110,25 +111,79 @@ public CartesianCoordinate GetCoordinate(double x, double y)
             return Coordinates.Find(c => { return c.X == x && c.Y == y; });
         }
 
+        /// <summary>
+        /// Ensure coordinates are sorted in a counter-clockwise position
+        /// </summary>
+        private void SortCoordinates()
+        {
+            var angles = new Dictionary<double,CartesianCoordinate>();
+
+            if (Coordinates.Count > 0)
+            {
+                foreach (var coordinate in Coordinates)
+                {
+                    angles.Add(coordinate.ToVector().Angle,coordinate);
+                }
+
+                angles.Values.ToList();
+
+                var list = angles.Keys.ToList();
+                list.Sort();
+
+                Coordinates.Clear();
+
+                foreach (var angle in list)
+                {
+                    Coordinates.Add(angles[angle]);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Determines whether a point is inside this polygonal area.
+        /// If the point is at an edge or a vertex it is considered to be
+        /// inside the area. It uses the algorithm documented by Paul Bourke.
+        /// <see href="http://web.archive.org/web/20080812141848/http://local.wasp.uwa.edu.au/~pbourke/geometry/insidepoly/"/>
+        /// </summary>
+        /// <param name="coordinate">The <see cref="CartesianCoordinate"/> that will be checked.</param>
+        /// <returns></returns>
         public bool CheckIfCoordinateIsInArea(CartesianCoordinate coordinate)
         {
             var isInside = false;
-            var x = coordinate.X;
-            var y = coordinate.Y;
+            int counter = 0;
+            int i = 1;
+            int n = Coordinates.Count;
+            double xinters;
+            CartesianCoordinate p1, p2;
 
-            var polySides = Coordinates.Count;
-            var j = polySides - 1;
+            p1 = Coordinates[0];
 
-            for (int i = 0; i < polySides; i++)
+            foreach (var point in Coordinates)
             {
-                if ((((Coordinates[i].Y < y && Coordinates[j].Y >= y) || (Coordinates[j].Y < y && Coordinates[i].Y >= y)) && (Coordinates[i].X <= x || Coordinates[j].X <= x)))
+                p2 = Coordinates[i % n];
+
+                if (coordinate.Y > Math.Min(p1.Y,p2.Y))
                 {
-                    isInside = isInside ^ ((Coordinates[i].X + (y - Coordinates[i].Y) / (Coordinates[j].Y - Coordinates[i].Y) * (Coordinates[j].X - Coordinates[i].X)) < x);
+                    if(coordinate.Y <= Math.Max(p1.Y,p2.Y))
+                    {
+                        if(coordinate.X <= Math.Max(p1.X,p2.X))
+                        {
+                            if(p1.Y != p2.Y)
+                            {
+                                xinters = (coordinate.Y - p1.Y) * (p2.X - p1.X) / (p2.Y - p1.Y) + p1.X;
+                                if (p1.X == p2.X || coordinate.X <= xinters) counter++;
+                            }
+                        }
+                    }
                 }
 
-                j = i;
+                p1 = p2;
+
+                i++;
             }
 
+            if (counter % 2 != 0) isInside = true;
+
             return isInside;
         }
     }
diff --git a/xDGA.CORE/xDGA.CORE.csproj b/xDGA.CORE/xDGA.CORE.csproj
index c27c024..0809f3c 100644
--- a/xDGA.CORE/xDGA.CORE.csproj
+++ b/xDGA.CORE/xDGA.CORE.csproj
@@ -20,6 +20,7 @@
     <DefineConstants>DEBUG;TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <DocumentationFile>bin\Debug\xDGA.CORE.xml</DocumentationFile>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
     <DebugType>pdbonly</DebugType>