1. Platinum Group Metal Flows of Europe, Part 1
2. 3) H. Nakajo and T. Nakamura: Technology of Alternatives and Recycling of Rare Metals, (CMC Publishing Co., Ltd., Tokyo, 2008) pp. 248-271.
3. 4) T. Okabe and H. Nakada: Technology of Alternatives and Recycling of Rare Metals, (CMC Publishing Co., Ltd., Tokyo, 2008) pp. 332-350.
4. 5) Web-Site of JOGMEC Mineral Resource Information Center: http://www.jogmec.go.jp/mric_web/jouhou/material/2008/PGM.pdf, (Status: 2010/Apr/15).