The ReiserFS filesystem
"This document describes the ReiserFS filesystem structures on disk. It was created while writing a ReiserFS reader for Windows NT. I was unsatisfied with the documentation available over at the official URL, www.namesys.com, so I wrote my own. But, since this is my first contact with ReiserFS, it does contain errors, so if in doubt, please consult the original spec first."
"This document is copyrighted by Gerson Kurz and licensed by the GPL."