Mohammad Iqbal wrote:

>Do you know where I can find the text and its translation to English that
>Mahler used in this huge symphony?

You should find it in the liner for most recordings.  The Solti, for
example.  Other than that, try Deryck Cooke's book on Mahler or the
Volume III of Henry-Louis de La Grange's biography.

Tony Duggan, England.
Mahler recordings survey:
http://www.musicweb.force9.co.uk/music/Mahler/