diff --git a/README b/README
index c6ae59f..89b17df 100644
--- a/README
+++ b/README
@@ -3,7 +3,7 @@ OpenSCAD MCAD Library
 
 This library contains components commonly used in designing and moching up mechanical designs. It is currently unfinished and still undergoing considerable API changes however many things are already working.
 
-This library is licensed under the GPL 3.0.
+This library currently has code licensed under the GPL 3.0 and GPL 2.0, please check the files for compatibility. This is to be remedied somehow soon.
 
 Currently Provided Tools:
 
diff --git a/constants.scad b/constants.scad
index 1ad2992..141c0c3 100644
--- a/constants.scad
+++ b/constants.scad
@@ -1,3 +1,6 @@
+// MIT license
+
+
 TAU = 6.2831853071; //2*PI, see http://tauday.com/
 PI = TAU/2;
 
diff --git a/curves.scad b/curves.scad
index 68102fd..87c675a 100644
--- a/curves.scad
+++ b/curves.scad
@@ -1,3 +1,7 @@
+// Parametric curves, to be used as paths
+// Licensed under the MIT license.
+// © 2010 by Elmo Mäntynen
+
 include <constants.scad>
 use <math.scad>
 
diff --git a/math.scad b/math.scad
index 19c3dd9..25b6721 100644
--- a/math.scad
+++ b/math.scad
@@ -1,3 +1,5 @@
+// MIT license
+
 include <constants.scad>
 
 function deg(angle) = 360*angle/TAU;