Le Bon Mariage has marginal notes which are linked by superscript letters in the text. This is our plan for dealing with them:

• The footnote letter in the text should be marked up like this:

  <hi rend="vertical-align: super;">a</hi>
  

• The marginal note should immediately follow it (assuming the note content appears level with it in the margin), and have a special @type attribute, like this:

  <note type="marginal" rend="float: right; width: 5em; [...etc.]"><ab>[content of the note]</ab></note>
  

  Note that the content appears inside an <ab> element, as in the case of a marginal <argument>.
• I'll have to write XSLT to distinguish between this and editorial types of note, and render this one just like marginal <argument>s.