diff --git a/SUMMARY.md b/SUMMARY.md
index 648eeb2..e3d9f54 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -55,9 +55,8 @@
     * [Fixmaps and ioremap](mm/linux-mm-2.md)
     * [kmemcheck](mm/linux-mm-3.md)
 * [Cgroups](Cgroups/README.md)
-    * [Introduction to Control Groups](Cgroups/cgroups1.md)
+    * [Introduction to Control Groups][Cgroups/cgroups1.md]
 * [SMP]()
-    * [Introduction](Cgroups/cgroups1.md)
 * [Concepts](Concepts/README.md)
     * [Per-CPU variables](Concepts/per-cpu.md)
     * [Cpumasks](Concepts/cpumask.md)
diff --git a/MM/README.md b/mm/README.md
similarity index 100%
rename from MM/README.md
rename to mm/README.md
diff --git a/MM/linux-mm-1.md b/mm/linux-mm-1.md
similarity index 100%
rename from MM/linux-mm-1.md
rename to mm/linux-mm-1.md
diff --git a/MM/linux-mm-2.md b/mm/linux-mm-2.md
similarity index 100%
rename from MM/linux-mm-2.md
rename to mm/linux-mm-2.md
diff --git a/MM/linux-mm-3.md b/mm/linux-mm-3.md
similarity index 100%
rename from MM/linux-mm-3.md
rename to mm/linux-mm-3.md