diff --git a/src/core/ngx_rbtree.h b/src/core/ngx_rbtree.h
index 04d7622..47ced3e 100644
--- a/src/core/ngx_rbtree.h
+++ b/src/core/ngx_rbtree.h
@@ -1,3 +1,9 @@
+
+/*
+ * Copyright (C) 2002-2004 Igor Sysoev
+ */
+
+
 #ifndef _NGX_RBTREE_H_INCLUDED_
 #define _NGX_RBTREE_H_INCLUDED_