var Whitepapers = $H();
var WhitepapersClass = Class.create({
    initialize: function() {
        $('WhitepapersForm').select('input[type=submit]').invoke('observe', 'click', function(e) {
            var bChecked = false;
            $('WhitepapersForm').select('input[type="checkbox"]').each(function(o) {
	            if (o.checked) {
                    $('WhitepapersForm').submit();
		            bChecked = true;
		            throw $break;
		        }
	        });
            if (!bChecked) alert('You have not selected any whitepapers!');
            e.stop();
        });
    }
});