RFC

If you want to view RFCs for anything, chances are you usually type RFC 5988 in google, and click on the first link that comes up, which is usually: http://www.ietf.org/rfc/rfc5988.txt

Well, truly so, this is the most authentic of results.

If you're a student who wants to acquaint with,  study or memorize the rfc, in which case you'd want a beautifully formatted pdf. But mostly, you want the rfc for a quick reference, or to confirm something you already know. In that case, you'd really like the rfc to be navigable, well if you view it like this:

http://tools.ietf.org/html/rfc5988

It will be, complete with links to references and document sections!