The 
                  braille element contains an alternative braille representation. It may contain preformatted braille text, or embed a format such
                  as PEF.
                  
               
The 
                  braille element contains an alternative braille representation. It may contain preformatted braille text, or embed a format such
                  as PEF.
                  
               
<d:tactile xml:id="tactile01">
    <d:braille>
        <pef xmlns="http://www.daisy.org/ns/2008/pef" version="2008-1">
            <head>...</head>
            <body>
                <volume cols="23" rows="12" rowgap="0" duplex="true">
                    <section>
                        <page>
                            <row>...</row>
                        </page>
                    </section>
                </volume>
            </body>
        </pef>
    </d:braille>
</d:tactile>
    This element may contain text or any elements.
braille element must neither be empty nor contain only whitespace.
                        
                     http://www.daisy.org/ns/z3998/authoring/features/description/