diff --git a/Example/Tests/MatrixSpec.swift b/Example/Tests/MatrixSpec.swift
index 776e6f0..a48aa85 100644
--- a/Example/Tests/MatrixSpec.swift
+++ b/Example/Tests/MatrixSpec.swift
@@ -51,6 +51,8 @@ class MatrixSpec: QuickSpec {
                             let adjugate = before.adjugate()
                             let inverse = before.inverse
                             expect(adjugate.zNormalized()) == inverse.zNormalized()
+                            expect(inverse.inverse) == before
+                            expect(simd_quaternion(adjugate.zNormalized())) == simd_quaternion(inverse.zNormalized())
                         }
                     }
                 #endif
diff --git a/Pod/Classes/Matrix3x3+3D.swift b/Pod/Classes/Matrix3x3+3D.swift
index ca3ef2a..41cc34c 100644
--- a/Pod/Classes/Matrix3x3+3D.swift
+++ b/Pod/Classes/Matrix3x3+3D.swift
@@ -23,9 +23,9 @@ extension Matrix3x3Type {
     }()
 
     func to3d() -> Matrix4x4Type {
-        var result = Matrix3x3Type.addRow * self * Matrix3x3Type.addColumn
-        result[2,2] = 1
-        return result
+        var stretch = Matrix3x3Type.addRow * self * Matrix3x3Type.addColumn
+        stretch[2,2] = 1
+        return stretch
     }
 
     func zNormalized() -> Matrix3x3Type {
@@ -50,7 +50,7 @@ extension Matrix3x3Type {
     }
 
     private func zNormalizedSafe() -> Matrix3x3Type {
-        return self[2,2]==0 ? self : zNormalizedUnsafe()
+        return self[2,2] == 0 ? self : zNormalizedUnsafe()
     }
 
     func adjugate()-> Matrix3x3Type {