<doc xml:base="one/two">
    <elem xml:base="http://example.org/one/two">
        http://example.org/one/two
    </elem>
    <elem xml:base="two2">
        ents/one/two2
    </elem>
    <elem xml:base="../one2/two">
        ents/one2/two
    </elem>
    <elem xml:base="../../../docs/one/two/three/four">
        docs/one/two/three/four
    </elem>
</doc>
