Please check this Jira issue conclusion

[Marshall Schor]

Mentors - can you please look at the comment trail in this Jira issue 
(https://issues.apache.org/jira/browse/UIMA-167) and see if you agree we 
can distribute the Docbook DTDs and Stylesheets under the Apache 
license, as part of our UIMA Source distribution?

Thanks. -Marshall