A sample xml file to demonstrate ruby libxml's reader api.
<?xml version="1.0" encoding="ISO-8859-1"?>
<nex:nexml
version="0.8"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.nexml.org/1.0 ../xsd/nexml.xsd"
xmlns:nex="http://www.nexml.org/1.0"
generator="mesquite"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns="http://www.nexml.org/1.0">
<otus
id="taxa1"
label="My taxa block"
xml:base="http://example.org/"
xml:id="taxa1"
class="taxset1"
xml:lang="EN"
xlink:href="#taxa1">
<!--
The taxon element is analogous to a single label in
a nexus taxa block. It may have the same additional
attributes (label, xml:base, xml:lang, xml:id, xlink:href
and class) as the taxa element.
-->
<otu id="t1"/>
<otu id="t2"/>
<otu id="t3"/>
<otu id="t4"/>
<otu id="t5"/>
</otus>
</nex:nexml>