function toggleauthors()

{
	try{
	var aut= document.getElementById('auth');
	var but = document.getElementById('authbutton');
	var tit = document.getElementById('authtitle');
	if (aut.style.display != "none")
	{
	    aut.style.display = "none";
	    but.src = "/bmcimages/expand2.gif";
	    tit.innerHTML = "authors";
	}
	else
	{
		aut.style.display = "block";
	 	but.src = "/bmcimages/contract2.gif";
	 	tit.innerHTML = "";
	}
	}
	catch(e){}
}