1. 1) Metal Mining Book; Japan Oil, Gas and Metals National Corporation （ JOGMEC）: Tokyo, p.161 （2008）
2. 2) Toshima, Y., A. Imai, K. Sanematsu, K. Yonezu, R. Takahashi, M. Koyama, R. Sekine, R. Duncan and K. Watanabe: "Characteristics and mineralization age of the Fukusen No. 1 vein, Hishikari epithermal gold deposits, southern Kyushu, Japan", Resour. Geol., 60, 348-358 （2010）
3. 3) Cui, J., L. Zhang : "Metallurgical recovery of metals from electronic waste : A review", J. Hazard. Mater., 158, 228-256 （2009）
4. 4) Global Mercury Assessment 2013, Sources, Emissions, Release and Environmental Transport, UNEP Chemical Branch, Geneva, Switzerland, p. 9 （2013）
5. 5) New Technology for Gold Recovery ; JOGMEC Report; Japan Oil, Gas and Metals National Corporation （ JOGMEC）: Tokyo （1995)