No permission to access Web Dynpro ABAP Tutorials ?

I am having dificulties accessing the tutorials for Web Dynpro ABAP. I can get to the 3 "Introductory Documents" but when I go to the "Tutorials" I can only access the first one (Web Dynpro for ABAP - Create a Simple Web Dynpro Application). The other 3 (Web Dynpro for ABAP - BAPI Usage, for example) I get the error below:

"403 Sorry, you do not have the correct

permissions to access this page."

Is this correct? If yes, it was not mentioned anyware else that part of the content was restricted.

Thanks