function show_picture(href, target) {
	var width = 400;
	var height = 280;
	var left = (screen.width - width) / 2;
	var top = (screen.height - height) / 2;
	window.open(href, target, 'width=' + width + ', height=' + height + ', left=' + left + ', top=' + top + ', location=no, toolbar=no, menubar=no, status=no');
	return false;
} // end function