function choser()
{
if (navigator.appName == "Netscape") window.open("atteveld/indexnet.html","_top");
else window.open("atteveld/indexint.html","_top");
}

function aanuit(wat,welke) 
{ 
document.all[welke].style.visibility=wat;
}

function aanuit(wat,welke) 
{ 
document.layers[welke].visibility=wat;
}