diff --git a/12.temporary_ins/05.coordinates-systems/30.cylindrical-coordinates/10.main/textbook.en.md b/12.temporary_ins/05.coordinates-systems/30.cylindrical-coordinates/10.main/textbook.en.md
index 2aa34c7b3..06a977add 100644
--- a/12.temporary_ins/05.coordinates-systems/30.cylindrical-coordinates/10.main/textbook.en.md
+++ b/12.temporary_ins/05.coordinates-systems/30.cylindrical-coordinates/10.main/textbook.en.md
@@ -3,6 +3,9 @@ title: Cylindrical coordinates
 published: true
 routable: false
 visible: false
+lessons:
+    - slug: cylindrical-coordinates-linear
+      order: 1
 ---