diff --git a/SUMMARY.md b/SUMMARY.md
index 3437415..39f399a 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -41,12 +41,13 @@
         * [Fabric](fabric/README.md)
         * [vRouter](vrouter/README.md)
 * [Modeling Guide](xos/README.md)
-    * [XOS Support for Models](xos/dev/xproto.md)
+    * [XOS Modeling Framework](xos/dev/xproto.md)
     * [Core Models](xos/core_models.md)
     * [Security Policies](xos/security_policies.md)
     * [Writing Synchronizers](xos/dev/synchronizers.md)
         * [Design Guidelines](xos/dev/sync_arch.md)
         * [Implementation Details](xos/dev/sync_impl.md)
+        * [Synchronizer Reference](xos/dev/sync_reference.md)
 * [Development Guide](developer/developer.md)
     * [Getting the Source Code](developer/getting_the_code.md)
     * [Developer Workflows](developer/workflows.md)