public function estimatesPrice($start_latitude, $start_longitude, $end_latitude, $end_longitude) {
        $path = '/v1/estimates/price';
        $parameters = array(
            'start_latitude' => $start_latitude,
            'start_longitude' => $start_longitude,
            'end_latitude' => $end_latitude,
            'end_longitude' => $end_longitude,
        );
        $result = $this->adapter->get($path, $parameters, $this->getHeaders());
        return $this->format($result);      
    }