diff --git a/doc/index.md b/doc/index.md
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--- a/doc/index.md
+++ /dev/null
@@ -1,10 +0,0 @@
-# Developer's Guide
-
- * [How to run from source tree](how_to_run.md)
- * [Directory Structure](directory.md)
- * [Mapping and Validation](mapping_and_validation.md)
- * [Authentication in Controller](authentication.md)
- * [About Action in Issue Comment](comment_actionb.md)
- * [Activity Types](activity.md)
- * [Notification Email](notification.md)
- * [Automatic Schema Updating](auto_update.md)
diff --git a/doc/readme.md b/doc/readme.md
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+# Developer's Guide
+
+ * [How to run from source tree](how_to_run.md)
+ * [Directory Structure](directory.md)
+ * [Mapping and Validation](mapping_and_validation.md)
+ * [Authentication in Controller](authentication.md)
+ * [About Action in Issue Comment](comment_actionb.md)
+ * [Activity Types](activity.md)
+ * [Notification Email](notification.md)
+ * [Automatic Schema Updating](auto_update.md)