nymous="1" ids="id2" refuri="http://external">

Corresponding references are linked via "refid" or resolved via "refuri"::

    <paragraph>
        <reference anonymous="1" refid="id1">
            text
        <reference anonymous="1" refuri="http://external">
            external
    <target anonymous="1" ids="id1">
    <target anonymous="1" ids="id2" refuri="http://external">
i¸