function toggle(button, id) {
          var target = document.getElementById(id);
          var button = document.getElementById(button);
          if (target != null) { 
              if (target.style.display == "block") {
                  target.style.display = "none";
                  button.style.background = 'url(/collection/euclid/images/tree_plus.gif) no-repeat center center';
                  button.setAttribute("title","more info");
              } else {
                  target.style.display = "block";
                  button.style.background = 'url(/collection/euclid/images/tree_minus.gif) no-repeat center center';
                  button.setAttribute("title","less info");
                  }
              }
          }

          function checkScript ( ) {
            if (document.primeTrial.inst.value == "") {
              alert( "Please enter your Institution name." );
              document.primeTrial.inst.focus();
              return false ;
            }
            if (document.primeTrial.addr1.value == "") {
              alert( "Please enter your address." );
              document.primeTrial.addr1.focus();
              return false ;
            }
            if (document.primeTrial.country_code.value == "") {
              alert( "Please select your country." );
              return false ;
            }
            if (document.primeTrial.inst_type.value == "") {
              alert( "Please select your institution type." );
              return false ;
            }
            if (document.primeTrial.user_pop.value == "") {
              alert( "Please enter your user population." );
              document.primeTrial.user_pop.focus();
              return false ;
            }
            if (document.primeTrial.name.value == "") {
              alert( "Please enter your name." );
              document.primeTrial.name.focus();
              return false ;
            }
            if (document.primeTrial.phone.value == "") {
              alert( "Please enter your phone." );
              document.primeTrial.phone.focus();
              return false ;
            }
            if (document.primeTrial.email.value == "") {
              alert( "Please enter your email." );
              document.primeTrial.email.focus();
              return false ;
            }
            return true ;
          }

        var mathmlCookieName  = "MathPlayerInstall";
        var mathmlCookieValue = "1";
        function getMathmlCookie(name) {
          var dc     = document.cookie;
          var prefix = name + "=";
          /**
           *  original code seems to be buggy
           *
           *  var begin  = dc.indexOf(";" + prefix);
           *  if (begin == -1) {
           *    begin = dc.indexOf(prefix);
           *    if (begin != 0) return null;
           *  } else {
           *    begin += 2;
           *  }
           *  var end = document.cookie.indexOf(";", begin);
           *  if (end == -1) {
           *    end = dc.length;
           *  }
           *  return unescape(dc.substring(begin + prefix.length, end));
           */
          var begin  = dc.indexOf(prefix);
          var end = document.cookie.indexOf(";", begin);
          if (end == -1) {
            end = dc.length;
          }
          return unescape(dc.substring(begin + prefix.length, end));
        }

        function checkForMathPlayer() {
          if( isIEWindows()) {
            if (ieVersion() >= 6.0) {
              if (isMPInstalled()) {       
                var start = navigator.appVersion.indexOf("MathPlayer");
                if (start != -1) { 
                } else {             
                  if ( getMathmlCookie(mathmlCookieName) != "true" ) {
                    window.showModelessDialog("/collection/euclid/mathml/updateMP_prompt.html", "",
                        "dialogWidth:600px;dialogHeight:200px;help:off;status:no");
                  }
                }
              } else {
                if ( getMathmlCookie(mathmlCookieName) != "true" ) {
                  window.showModelessDialog("/collection/euclid/mathml/noMP_prompt.html", "", 
                      "dialogWidth:600px;dialogHeight:200px;help:off;status:no");
                }
              }
            } else { 
            }
          } else { 
          }
        }
        
        function isMPInstalled() {
          try {
            var oMP = new ActiveXObject("MathPlayer.Factory.1");
            return true;
          } catch(e) {
            return false;
          }
        }

        function isIEWindows() {
          return( (navigator.appName=="Microsoft Internet Explorer") && 
            (navigator.appVersion.indexOf("Windows") != -1) );
        }

        function ieVersion() {
          var ieVer = 0;
          var start = navigator.appVersion.indexOf("MSIE "); 
          if (start != -1) { 
            ieVer = parseFloat(navigator.appVersion.substring(start+5)); 
          }
          return ieVer;
        }

        checkForMathPlayer();

function convertMath(node) {// for Gecko
  if (node.nodeType==1) {
    var newnode = 
      document.createElementNS("http://www.w3.org/1998/Math/MathML",
        node.nodeName.toLowerCase());
    for(var i=0; i < node.attributes.length; i++)
      newnode.setAttribute(node.attributes[i].nodeName,
        node.attributes[i].nodeValue);
    for (var i=0; i<node.childNodes.length; i++) {
      var st = node.childNodes[i].nodeValue;
      if (st==null || st.slice(0,1)!=" " && st.slice(0,1)!="\n") 
        newnode.appendChild(convertMath(node.childNodes[i]));
    }
    return newnode;
  }
  else return node;
}
function convert() {
  var mmlnode = document.getElementsByTagName("math");
  var st,str,node,newnode;
  for (var i=0; i<mmlnode.length; i++)
    if (document.createElementNS!=null)
      mmlnode[i].parentNode.replaceChild(convertMath(mmlnode[i]),mmlnode[i]);
    else { // convert for IE
      str = "";
      node = mmlnode[i];
      while (node.nodeName!="/MATH") {
        st = node.nodeName.toLowerCase();
        if (st=="#text") str += node.nodeValue;
        else {
          str += (st.slice(0,1)=="/" ? "</m:"+st.slice(1) : "<m:"+st);
          if (st.slice(0,1)!="/") 
             for(var j=0; j < node.attributes.length; j++)
               if (node.attributes[j].nodeValue!="italic" &&
                 node.attributes[j].nodeValue!="" &&
                 node.attributes[j].nodeValue!="inherit" &&
                 node.attributes[j].nodeValue!=undefined)
                 str += " "+node.attributes[j].nodeName+"="+
                     "\""+node.attributes[j].nodeValue+"\"";
          str += ">";
        }
        node = node.nextSibling;
        node.parentNode.removeChild(node.previousSibling);
      }
      str += "</m:math>";
      newnode = document.createElement("span");
      node.parentNode.replaceChild(newnode,node);
      newnode.innerHTML = str;
    }
}