private function _makeOAuthCall($apiData)
    {
        $apiHost = self::API_OAUTH_TOKEN_URL;

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $apiHost);
        curl_setopt($ch, CURLOPT_POST, count($apiData));
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($apiData));
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Accept: application/json'));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_TIMEOUT, 90);
        $jsonData = curl_exec($ch);

        if (!$jsonData) {
            throw new InstagramException('Error: _makeOAuthCall() - cURL error: ' . curl_error($ch));
        }

        curl_close($ch);

        return json_decode($jsonData);
    }