Fixed ref in doc

docs/src/concepts.rst

@@ -18,7 +18,7 @@ It is initialized through MODULE macro:
     
 This macro creates a "test" module. |br|
 MODULE macro also creates a constructor and destructor that are automatically called by libmodule at start and at end of program. |br|
-Finally, this macro declares all of needed callbacks and returns an opaque handler for the module, that will be transparently passed with each call to libmodule API while using easy AP:ref:`module_easy`. |br|
+Finally, this macro declares all of needed callbacks and returns an opaque handler for the module, that will be transparently passed with each call to libmodule API while using :ref:`module_easy`. |br|
 
 Submodule concept
 -----------------