# cat /etc/apt/sources.list
deb http://it.archive.ubuntu.com/ubuntu/ utopic main
deb-src http://it.archive.ubuntu.com/ubuntu/ utopic main

deb http://security.ubuntu.com/ubuntu utopic-security main
deb-src http://security.ubuntu.com/ubuntu utopic-security main

#deb http://it.archive.ubuntu.com/ubuntu/ utopic-updates main universe restricted multiverse
#deb-src http://it.archive.ubuntu.com/ubuntu/ utopic-updates main universe restricted multiverse

# cat /etc/apt/sources.list.save
deb http://archive.ubuntu.com/ubuntu precise main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu precise-updates main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu precise-security main restricted universe multiverse
deb http://archive.canonical.com/ubuntu precise partner