function(popForward){
var popImage1 = document.getElementById('popForward');
popImage1.src = "../images/pageTurnForward.gif";
popImage1.style.visibility="visible";
}

function(popBackward){
var popImage2 = document.getElementById('popBackward');
popImage2.src = "../images/pageTurnBack.gif";
popImage2.style.visibility="visible";
}

function msieversion(){
var ua = window.navigator.userAgent
var msie = ua.indexOf ( "MSIE " )
if ( msie > 0 )
return parseInt (ua.substring (msie+5, ua.indexOf (".", msie )))
else
return 0
}