CentralBodyReferenceSystemBuilder.md

@@ -18,6 +18,8 @@ final CentralBodyReferenceSystem system = CentralBodyReferenceSystem.builder().w
 
 `withName(String name)` - CentralBodyReferenceSystemBuilder : Add a name for the central reference system.
 
+`withHeader`([Header](Header) header) - LineOfVisibilityBuilder : Add a header as a reference, when several header are used.
+
 ## The build function
 
 In order to generate the line of visibility don't forget to add the `build()` function.
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