diff --git a/SUMMARY.md b/SUMMARY.md
index 5412e09..1a917d2 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -3,4 +3,5 @@
 * [Einleitung](README.md)
 * [01 Einführung in Discovery-Systeme in Bibliotheken](01_Einfuehrung-Discovery-Systeme.md)
    * [Marktüberblick](01_3_marktueberblick.md)
+   * OPAC vs. Discovery-System