f them come in a group of three, one prefixed with the string <code class="function">START</code>, another with no prefix, and the last one with the prefix
      <code class="function">END</code>. (For example, <code class="function">:STARTSLUR-</code>, <code class="function">:SLUR-</code> and <code class="function">:ENDSLUR-</code>.) 
      Spanner marks may be indicated in two different ways:
      </p><div class="itemizedlist"><ul type="disc"><li><p>
	  The <code class="function">START</code> and <code c