When I run apt-get update I get some failures at the end and I'd like to remove them but I don't know which PPA they are coming from. I have Y-PPA Manager installed, but still can't find where it is coming from.
Ign http://packages.medibuntu.org raring/non-free Translation-en
Err http://packages.medibuntu.org raring/free amd64 Packages
404 Not Found
Err http://packages.medibuntu.org raring/non-free amd64 Packages
404 Not Found
Err http://packages.medibuntu.org raring/free i386 Packages
404 Not Found
Err http://packages.medibuntu.org raring/non-free i386 Packages
404 Not Found
Ign http://us.archive.ubuntu.com raring/main Translation-en_US
Ign http://us.archive.ubuntu.com raring/multiverse Translation-en_US
Ign http://us.archive.ubuntu.com raring/restricted Translation-en_US
Ign http://us.archive.ubuntu.com raring/universe Translation-en_US
Ign http://us.archive.ubuntu.com raring-updates/main Translation-en_US
Ign http://us.archive.ubuntu.com raring-updates/multiverse Translation-en_US
Ign http://us.archive.ubuntu.com raring-updates/restricted Translation-en_US
Ign http://us.archive.ubuntu.com raring-updates/universe Translation-en_US
Ign http://us.archive.ubuntu.com raring-backports/main Translation-en_US
Ign http://us.archive.ubuntu.com raring-backports/multiverse Translation-en_US
Ign http://us.archive.ubuntu.com raring-backports/restricted Translation-en_US
Ign http://us.archive.ubuntu.com raring-backports/universe Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_US
Ign http://ppa.launchpad.net raring/main Translation-en
Fetched 1,302 kB in 17s (73.2 kB/s)
W: Failed to fetch http://packages.medibuntu.org/dists/raring/free/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://packages.medibuntu.org/dists/raring/non-free/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://packages.medibuntu.org/dists/raring/free/binary-i386/Packages 404 Not Found
W: Failed to fetch http://packages.medibuntu.org/dists/raring/non-free/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
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