public function encodeControlAttribution(Attribution $attribution, Encoder $encoder)
    {
        $result = $this->doControlEncode('attribution', $attribution, $encoder);

        foreach ($attribution->getAttributions() as $value) {
            $result .= sprintf(
                '%s.addAttribution(\'%s\');' . "\n",
                $encoder->encodeReference($attribution),
                $value
            );
        }

        return $result;
    }