function list_show_city() {
	var v,obj;
	if ((obj=MM_findObj('list_show_city'))!=null) {
		if (document.layers) {
			v = obj['display'];
			obj['display'] = ((v=='block')?'none':'block');
		} else {
			v = obj.style['display'];
			obj.style['display'] = ((v=='block')?'none':'block');
		}
	}
	return false;
}