function select_tab(obj){
	// get the parent h1 tag
	var parent_tag = obj.parentNode.parentNode;
	// get all anchor tags inside the parent_tag
	var child_tags = parent_tag.getElementsByTagName('a');
	// loop thru and replace any <b> tags with <i> tags (and make current selection <b>)
	for(var i = 0; i < child_tags.length; i++){
		var oldnode = child_tags[i].parentNode;
		var newnode = (obj==child_tags[i])?document.createElement('b'):document.createElement('i');
		newnode.appendChild(child_tags[i]);
		parent_tag.replaceChild(newnode,oldnode);
		// work out which divs to hide / show
		var divid = child_tags[i].href.substr(child_tags[i].href.indexOf('#')+1);
		document.getElementById(divid).style.display = (obj==child_tags[i])?'block':'none';
		}
	return false;
	}