function openRef1()
{
    str='http://www.panoview.nl/tours/website/voorbeelden/1' ;
    isn = window.open(str,'isn','width=584,height=621,left=100,top=140,statusbar=yes,scrollbars=no');
    isn.opener = self;
}

function openRef2()
{
    str='http://www.panoview.nl/tours/website/voorbeelden/2' ;
    isn = window.open(str,'isn','width=584,height=621,left=100,top=140,statusbar=yes,scrollbars=no');
    isn.opener = self;
}

function openRef3()
{
    str='http://www.panoview.nl/tours/website/voorbeelden/3' ;
    isn = window.open(str,'isn','width=584,height=621,left=100,top=140,statusbar=yes,scrollbars=no');
    isn.opener = self;
}

function openRef4()
{
    str='http://www.panoview.nl/tours/website/voorbeelden/4' ;
    isn = window.open(str,'isn','width=584,height=621,left=100,top=140,statusbar=yes,scrollbars=no');
    isn.opener = self;
}