Can't install nginx from nginx.org repository on ubuntu server 13.04?

Question

linux

Ubuntu Server 13.04 x64
I'm trying to install nginx according to the instructions nginx.org/en/linux_packages.html
I'm doing :

wget http://nginx.org/keys/nginx_signing.key
sudo apt-key add nginx_signing.key

sudo sh -c "echo 'deb http://nginx.org/packages/debian/ raring nginx' >> /etc/apt/sources.list"

sudo sh -c "echo 'deb-src http://nginx.org/packages/mainline/debian/ raring nginx' >> /etc/apt/sources.list"

sudo apt-get update

After sudo apt-get update I get

nginx.org raring /nginx amd64 Packages
404 Not Found
nginx.org raring / nginx i386 Packages
404 Not Found
nginx.org raring / nginx nginx Translation-en Error nginx.org raring /nginx Sources 404 Not Found W: Failed to get nginx.org/packages/debian/dists/raring/nginx/binar... 404 Not Found W: Failed to get nginx.org/ packages/debian/dists/raring/nginx/binar... 404 Not Found W: Failed to get
nginx.org/packages/mainline/debian/dists/raring/ng... 404 Not Found
E: Some index files were not downloaded. They were ignored or older versions were used instead.

Please tell me what am I doing wrong?

Answer 1

Changed to
deb http://nginx.org/packages/ubuntu/ codename nginx
deb-src http://nginx.org/packages/ubuntu/ codename nginx
and everything worked. Simple inattention

Answer 2

There is no support for the raring distribution.
There is only wheezy and squeeze.
See for yourself at the link you add to /etc/apt/sources.list