diff --git a/SUMMARY.md b/SUMMARY.md
index 305895f65839dadf0b8ffd64aa41f7e9d2444b04..89db1049cb164abb5a97eac65537b801169d1bc5 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -48,6 +48,7 @@
     * [Lists and List-Operations](./1-04-0-lists.md)
     * [Extra Credit: Look-up Lists and Trees](./1-05-0-lookups-trees.md)
     * [Numbers and Math](./1-06-0-math.md)
+        * [Integers](./1-06-01-integers.md)
     * [Extra Credit: Arrays and Vectors](./1-07-0-arrays.md)
     * [Variables, Parameters, and Constants](./1-08-0-variables.md)
     * [Extra Credit: Closures](./1-09-0-closures.md)