How to use GFDL 1.1

[Alexander Shopov <al_shopov web bg>]

Hi guys,
I am currently writing a mini-howto on translating the Gnome interface
in Bulgarian.
I want to release it under GFDL.
I am not sure whether I must have things like Invariant sections, cover
and back texts.
What is the intent of such sections?
Another question - GFDL is quite big, can I just make a reference to it
online and point
people to FSF for a written copy if they want it? (like GPL says?)
al_SHOPOV