<lg><l>The self-same moment I could pray></l> 
<l>And from my neck so free</l>
<l>The albatross fell off, and sank</l>
<l>Like lead into the sea. 
<note type="auth" place="margin"> 
The spell begins to break.</note> </l> 
</lg>

or

...
<l>The albatross fell off, and sank</l>
<l xml:id="L213">Like lead into the sea. </l> 
</lg>
...
<note type="auth" place="margin" target="#L213"> 
The spell begins to break.</note>