rk sign,
                                  U+00AE ISOnum --&gt;
&lt;!ENTITY macr   CDATA "&amp;#175;" -- macron = spacing macron = overline
                                  = APL overbar, U+00AF ISOdia --&gt;
&lt;!ENTITY deg    CDATA "&amp;#176;" -- degree sign, U+00B0 ISOnum --&gt;
&lt;!ENTITY plusmn CDATA "&amp;#177;" -- plus-minus sign = plus-or-minus sign,
                                  U+00B1 ISOnum --&gt;
&lt;!ENTITY sup2   CDATA "&amp;#178;" -- superscript two = superscript digit two
            