$ cat /etc/apt/sources.list
deb http://ftp.de.debian.org/debian/ wheezy main non-free contrib
deb-src http://ftp.de.debian.org/debian/ wheezy main non-free contrib
deb http://ftp.de.debian.org/debian wheezy-backports main non-free contrib
deb-src http://ftp.de.debian.org/debian/ wheezy main non-free contrib

deb http://security.debian.org/ wheezy/updates main non-free contrib
deb-src http://security.debian.org/ wheezy/updates main non-free contrib