Japan. Kankyōshō. Risaikuru Suishinshitsu

• Hai petto botoru no yushutsu tō shichōson ni okeru dokuji shori ni kansuru jittai chōsa hōkokusho
• Heisei 19-nendo yōki hōsō haikibutsu no tentō kaishū ni kansuru ankēto chōsa hōkokusho