function popupWinSmall(url)
{
    window.open(url, 'intro', 'width=400,height=300,scrollbars=yes,toolbar=no,location=no');
    return false;
}

function popupWinMedium(url)
{
    window.open(url, 'intro', 'width=700,height=500,scrollbars=no,toolbar=no,resizable=no');
}

function popupWinLarge(url)
{
    window.open(url, 'intro', 'width=800,height=600,scrollbars=yes,toolbar=no,resizable=yes');
}