diff --git a/X10D.Tests/src/Drawing/PolygonTests.cs b/X10D.Tests/src/Drawing/PolygonTests.cs
index 8d3c483..639eec9 100644
--- a/X10D.Tests/src/Drawing/PolygonTests.cs
+++ b/X10D.Tests/src/Drawing/PolygonTests.cs
@@ -1,4 +1,4 @@
-using System.Drawing;
+using System.Drawing;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using X10D.Drawing;
 
@@ -27,7 +27,7 @@ public class PolygonTests
         Assert.AreEqual(2, polygon.VertexCount);
 
         // assert that the empty polygon was not modified
-        Assert.AreEqual(0, PolygonF.Empty.VertexCount);
+        Assert.AreEqual(0, Polygon.Empty.VertexCount);
 
         polygon.ClearVertices();
         Assert.AreEqual(0, polygon.VertexCount);