diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 3b243fea..afcc6eea 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -37,3 +37,5 @@ Richard Coates
 THANOS SIOURDAKIS
 Toover
 Xavier Mehrenberger
+
+The manual drawings are from Coline, they are under CC BY 4.0.