• Sources.list generator - Ubuntu - Linux for Human Beings
  Here you can generate an ubuntu sources.list for your preferred set of repositories. Just tick all repositories you want. The default set is selected automatically. If you know another repository that should be included here, feel free to send your suggestion to dennis@ubuntu.com When a repository in this list has a GPG key, you may need to add that to the APT trusted keys. You can do this with the following commands (replace KEY with the key ID)
  "Ubuntu" is an ancient African word, meaning "humanity to others". Ubuntu also means "I am what I am because of who we all are". The Ubuntu Linux distribution brings the spirit of Ubuntu to the software world.
  in Computing > Linux > Howto with automatically commands computer computing gpg key keys linux repositories repository sources.list ubuntu by 6 users
  Note: Now this is the shizal. Have a read of this too: http://ubuntuforums.org/showthread.php?t=230057

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