diff --git a/todo2.txt b/todo2.txt
index 104e015..dd24a51 100644
--- a/todo2.txt
+++ b/todo2.txt
@@ -19,3 +19,5 @@ http://en.wikipedia.org/wiki/List_of_C%2B%2B_template_libraries
 http://www.csie.ntu.edu.tw/~cjlin/liblinear/
 http://www.csie.ntu.edu.tw/~cjlin/libsvmtools/
 
+-------------------------------------
+https://cryptocoding.net/index.php/Coding_rules#Clean_memory_of_secret_data