Prefered Licence

[Pierre-Yves Luyten <py luyten fr>]

Hi,

Which is the best licence for manuals, GFDL 1.1 / Creative Commons ? 

Obviously this is not for troll but necessary information to choose
which one.

As I used existing material as a basis for a new manual, I re-used GFDL
(1.1) licence from old one. But if Creative Common is rather preferred I
can still try to reach authors to re-licence.

Thanks
Pierre-Yves