diff --git a/Circular_kernel_2/TODO b/Circular_kernel_2/TODO
index c8c4a37ae9e..67cd464c1d3 100644
--- a/Circular_kernel_2/TODO
+++ b/Circular_kernel_2/TODO
@@ -1,3 +1,5 @@
+heriter result_type des foncteurs du Kernel (Bool_type \neq bool...)
+
 fix manual for operator>>
 
 manual filtered bbox kernel, ref counting