diff --git a/TODO b/TODO
index fee48a3..a179724 100644
--- a/TODO
+++ b/TODO
@@ -136,3 +136,8 @@ https://www.youtube.com/watch?v=nyNCSM4vGF4
 ----- File System
 
 https://developer.ibm.com/tutorials/l-virtual-filesystem-switch/
+
+
+------------ Persistent memory
+
+https://github.com/pmem/book