diff --git a/LICENSE.txt b/LICENSE.txt
index e6f1803..efc2acc 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -12,6 +12,8 @@ Schematics CC-BY-SA
   (Creative Commons Attribution Share Alike)
   per github.com/gexpander/gex-hardware
 
+References attached for convenience retain their original copyright (see the files for details)
+
 ---
 
 Macros and other LaTeX code may be reused freely.