<document source="test data">
    <paragraph>
        <reference refuri="http://www.standalone.hyperlink.com">
            http://www.standalone.hyperlink.com
    <paragraph>
        <reference refuri="http:/one-slash-only.absolute.path">
            http:/one-slash-only.absolute.path
    <paragraph>
        [
        <reference refuri="http://example.com">
            http://example.com
        ]
    <paragraph>
        (
        <reference refuri="http://example.com">
            http://example.com
        )
    <paragraph>
        <
        <reference refuri="http://example.com">
            http://example.com
        >
    <paragraph>
        <reference refuri="http://[1080:0:0:0:8:800:200C:417A]/IPv6address.html">
            http://[1080:0:0:0:8:800:200C:417A]/IPv6address.html
    <paragraph>
        <reference refuri="http://[3ffe:2a00:100:7031::1]">
            http://[3ffe:2a00:100:7031::1]
         (the final "]" is ambiguous in text)
    <paragraph>
        <reference refuri="http://[3ffe:2a00:100:7031::1]/">
            http://[3ffe:2a00:100:7031::1]/
    <paragraph>
        <reference refuri="mailto:someone@somewhere.com">
            mailto:someone@somewhere.com
    <paragraph>
        <reference refuri="news:comp.lang.python">
            news:comp.lang.python
    <paragraph>
        An email address in a sentence: 
        <reference refuri="mailto:someone@somewhere.com">
            someone@somewhere.com
        .
    <paragraph>
        <reference refuri="ftp://ends.with.a.period">
            ftp://ends.with.a.period
        .
    <paragraph>
        (
        <reference refuri="mailto:a.question.mark@end">
            a.question.mark@end
        ?)