function queryString( parameter ) {
	var loc = location.search.substring(1, location.search.length);
	var param_value = false;
	var params = loc.split("&");
	for (i=0; i<params.length;i++) {
		param_name = params[i].substring(0,params[i].indexOf('='));
		if (param_name == parameter) {
			param_value = params[i].substring(params[i].indexOf('=')+1)
		}
	}
	if (param_value) {
		return param_value;
	} else {
		return '';
	}
}