I understood that I have to go to the Download Centre.
It says "For the 2013 version, all three disciplines of Revit Architecture, MEP, and Structure) are included in one unified interface. If you are interested in a 2013 version, please download Revit 2013 from this catalog."
Which catalog? I don't see it. Help please? Or just give me the direct link to dowload it?
Were you trying to download it from the Education Community Site? I checked using my account and I was able to see Autodesk Revit 2013 and download it without any other requirements. See attached.
However, when I checked your account I can see that your account is one of those affected by the issue we had with the site. I suggest that you create a new account with a different email address. Once you have the new account and you still cannot see the Autodesk Revit 2013, let me know.