RE: Change language. POST or GET

Maybe I have express myself wrong. I will try again with an example:

I am abroad, using a shared pc with arabic language as default. I send a
request to the URL http://www.example.org/doc. By content negociation, a
server will response with a page written in arabic. In that moment, I
want to change the language of the content, and the return page should
be again http://www.example.org/doc.

What would be the correct approach ?
- a link that invokes a HTTP GET method
- a button that invokes a HTTP POST method

Carlos Tejo Alonso
R&D and Innovation Department - CTIC Foundation [Asturias, Spain]
www.fundacionctic.org