Twin directories of 3.1_r8:

[DIR]  ftp://ftp.gnome.org/cdimage/archive/3.1_r8/
[DIR]  ftp://24.215.0.24/Debian/debian-jigdo/3.1_r8/
[DIR]  ftp://139.124.132.163/debian-cd/jigdo/stable/3.1_r8/
[DIR]  ftp://ftp.usc.es/pub/mirror/linux/debian-jigdo/3.1_r8/