[Doxygen-users] Grouping Pages?

[Christoph L. <chr...@li...>]

In addition to in-source docs, our project also uses various markdown 
pages providing additional information. At present, they all show up at 
the top level of the main index, like so:

     Extra Page 1
     Extra Page 2A
     Extra Page 2B
     Extra Page 3
     Todo List
     Deprecated List
     Namespaces
     Classes
     Files

Now I would like to group Extra Pages 2A and 2B together in the index, 
while still keeping them as separate HTML pages, like so:

     Extra Page 1
     Extra Page 2
         Extra Page 2A
         Extra Page 2B
     Extra Page 3
     Todo List
     ...

is that possible with Doxygen?