public static function getNumberingTypeAsRtf($numbering, $prefix = '\ftnn')
    {
        switch ($numbering) {
            default:
                // const name NUMTYPE_ARABIC_NUMBERS
                return $prefix . 'ar';
            case PHPRtfLite_Footnote::NUMTYPE_ALPHABETH_LC:
                return $prefix . 'alc';
            case PHPRtfLite_Footnote::NUMTYPE_ALPHABETH_UC:
                return $prefix . 'auc';
            case PHPRtfLite_Footnote::NUMTYPE_ROMAN_LC:
                return $prefix . 'rlc';
            case PHPRtfLite_Footnote::NUMTYPE_ROMAN_UC:
                return $prefix . 'ruc';
            case PHPRtfLite_Footnote::NUMTYPE_CHICAGO;
                return $prefix . 'chi';
            case PHPRtfLite_Footnote::NUMTYPE_KOREAN_1:
                return $prefix . 'chosung';
            case PHPRtfLite_Footnote::NUMTYPE_KOREAN_2:
                return $prefix . 'ganada';
            case PHPRtfLite_Footnote::NUMTYPE_CIRCLE:
                return $prefix . 'cnum';
            case PHPRtfLite_Footnote::NUMTYPE_KANJI_1:
                return $prefix . 'dbnum';
            case PHPRtfLite_Footnote::NUMTYPE_KANJI_2:
                return $prefix . 'dbnumd';
            case PHPRtfLite_Footnote::NUMTYPE_KANJI_3:
                return $prefix . 'dbnumt';
            case PHPRtfLite_Footnote::NUMTYPE_KANJI_4:
                return $prefix . 'dbnumk';
            case PHPRtfLite_Footnote::NUMTYPE_DOUBLE_BYTE:
                return $prefix . 'dbchar';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_1:
                return $prefix . 'gbnum';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_2:
                return $prefix . 'gbnumd';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_3:
                return $prefix . 'gbnuml';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_4:
                return $prefix . 'gbnumk';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_ZODIAC_1:
                return $prefix . 'zodiac';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_ZODIAC_2:
                return $prefix . 'zodiacd';
            case PHPRtfLite_Footnote::NUMTYPE_CHINESE_ZODIAC_3:
                return $prefix . 'zodiacl';
        }
    }