private function addExponents($minute = '', array $exponents = [], $notesType = null)
    {
        $cleanedExposents = array_filter($exponents);

        $exposantsNb = count($cleanedExposents);

        if ($notesType == LayoutConfig::NOTES_TYPE_COLOR && $exposantsNb < 2) {
            return $minute;
        }

        array_walk($cleanedExposents, function (&$value) {
            $value = sprintf('<sup>%s</sup>', $value);
        });

        return $minute . join('', $cleanedExposents);
    }