Index: Include/Classes/System/Math.ab
===================================================================
--- Include/Classes/System/Math.ab	(revision 20)
+++ Include/Classes/System/Math.ab	(revision 23)
@@ -546,8 +546,8 @@
 					last = Sqrt
 					Sqrt = (x /Sqrt + Sqrt) * 0.5
-				Loop While s <> last
+				Loop While Sqrt <> last
 			End If
 		ElseIf x < 0 Then
-			Sqr = _System_GetNaN()
+			Sqrt = _System_GetNaN()
 		Else
 			'x = 0 Or NaN