diff --git a/pages/docs/index.md b/pages/docs/index.md
index ea3389903e2913926cada1448e0fc4e7a78503d6..b0f6675264020f9362f6065b4f0c00d219b81e19 100644
--- a/pages/docs/index.md
+++ b/pages/docs/index.md
@@ -32,15 +32,17 @@ There are some implementation details developers must consider:
     - `ServerVariablesTuple ::= <Name> S:ServerVariableObject;` 
     - `variables` in [Server Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#serverObject)
 
-- In OAS, several objects can be replaced by [Reference Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#referenceObject). In `RAGO`, we implemented this structure in an abstract node to every concerned object. 
-
+- In OAS, several objects can be replaced by [Reference Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#referenceObject). In `RAGO`, we implemented this structure in an abstract node to every concerned object. e.g. 
+    - [Parameter Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#parameterObject)
+    - following abstract node in JastAdd
+  
 
+Example of [Parameter Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#parameterObject) implementation
 ``` 
   abstract ParameterOb;
   ParameterReference : ParameterOb ::= <Ref> ...;
   ParameterObject : ParameterOb ::= <Name> <In> ...;
- ```
-Example to implementation of [Reference Object](https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#referenceObject)
+```
 
 
 - Most objects can be extended with `Extension` containing unfixed name and values. In JastAdd, this is also implemented in a tuple (AST-Node) `Extension ::= <Key> <Value:Object>;`