diff --git a/BasicGeometry/FP32Versor.cs b/BasicGeometry/FP32Versor.cs
index 0912aab..ae923c3 100644
--- a/BasicGeometry/FP32Versor.cs
+++ b/BasicGeometry/FP32Versor.cs
@@ -100,7 +100,7 @@ namespace BasicGeometry
                 return FP32Angle.GetHalfCircle(unit);
             }
 
-            return FP32Radians.ToUnits(2.0f * MathF.Acos(s0), unit);
+            return FP32Radians.ToUnits(2.0f * MathF.Acos(this.s0), unit);
         }
 
         public readonly void MakeRotationMatrix(out FP32Matrix3x3 matrix)
diff --git a/BasicGeometry/FP64Versor.cs b/BasicGeometry/FP64Versor.cs
index bd1396e..b750c4e 100644
--- a/BasicGeometry/FP64Versor.cs
+++ b/BasicGeometry/FP64Versor.cs
@@ -103,7 +103,7 @@ namespace BasicGeometry
                 return FP64Angle.GetHalfCircle(unit);
             }
 
-            return FP64Radians.ToUnits(2.0 * Math.Acos(s0), unit);
+            return FP64Radians.ToUnits(2.0 * Math.Acos(this.s0), unit);
         }
 
         public readonly void MakeRotationMatrix(out FP64Matrix3x3 matrix)
@@ -254,12 +254,12 @@ namespace BasicGeometry
                 return;
             }
 
-            double module = Math.Sqrt(squareModule);
+            double multiplier = Math.Sqrt(1.0 / squareModule);
 
-            this.s0 /= module;
-            this.x1 /= module;
-            this.x2 /= module;
-            this.x3 /= module;
+            this.s0 *= multiplier;
+            this.x1 *= multiplier;
+            this.x2 *= multiplier;
+            this.x3 *= multiplier;
         }
 
         public static void Combine(in FP64Versor second, in FP64Versor first, out FP64Versor result)