fix several bad links

Author: davidcarlisle

src/fundamentals.html

@@ -753,7 +753,7 @@ <h3 id="interf_toplevel">The Top-Level
    <h4 id="interf_toplevel_atts">Attributes</h4>
 
    <p>The <code class="element">math</code> element accepts any of the common presentation attributess specified in
-   <a id="presm_presatt">Mathematics attributes common to presentation elements</a>,
+   <a href="#presm_presatt">Mathematics attributes common to presentation elements</a>,
    along with the common attributes
    specified in <a href="#fund_globatt"></a>.
    In particular, it accepts the <code class="attribute">dir</code> attribute for

src/presentation-markup.html

@@ -574,7 +574,7 @@ <h4 id="presm_scriptlevel">Displaystyle and Scriptlevel</h4>
    becoming unreadably small.
    The default <code class="attribute">scriptsizemultiplier</code> is approximately the square root of 1/2
    whereas <code class="attribute">scriptminsize</code> defaults to 8 points;
-   these values may be changed on any presentation element; see  <a href="#"presm_presatt_core">MathML Core Attributes"></a>.
+   these values may be changed on any presentation element; see  <a href="#presm_presatt_core">MathML Core Attributes"></a>.
    Note that the <code class="attribute">scriptlevel</code> attribute allows arbitrary
    values of <code class="attribute">scriptlevel</code> to be obtained, including negative values which
    result in increased font sizes.
@@ -1025,7 +1025,7 @@ <h5 id="presm_presatt_core">MathML Core Attributes</h5>
    to be semantically different than a black "x", in contrast to
    variables with different <code class="attribute">mathvariant</code> values (see <a href="#presm_commatt"></a>).
    The remaining two override some default rules for layout of expressions.
-   See <a href="#presm.scriptlevel">Section&nbsp;3.1.6 Displaystyle and Scriptlevel</a> for more information</p>
+   See <a href="#presm_scriptlevel"></a> for more information</p>
 
    <table class="attributes data">
 
@@ -1076,7 +1076,7 @@ <h5 id="presm_presatt_core">MathML Core Attributes</h5>
        <tr>
         <td colspan="2" class="attdesc">
         Changes the <code class="attribute">displaystyle</code> in effect for the children.
-        See <a href="#presm.scriptlevel">Section&nbsp;3.1.6 Displaystyle and Scriptlevel</a>.
+        See <a href="#presm_scriptlevel"></a>.
       </td>
       </tr>
       <tr>
@@ -1087,7 +1087,7 @@ <h5 id="presm_presatt_core">MathML Core Attributes</h5>
       <tr>
         <td colspan="2" class="attdesc">
           Changes the <code>displaystyle</code> in effect for the children.
-          See <a href="#presm.scriptlevel">Section&nbsp;3.1.6 Displaystyle and Scriptlevel</a>.
+          See <a href="#presm_scriptlevel"></a>.
         </td>
       </tr>      
 </tbody>