Chen YS, Lin YE, Liu YC, Huang WK, Shih HY, Wann SR, Lee SS, Tsai HC, Li CH, Chao HL, Ke CM, Lu HH, Chang CL. “Efficacy of point-of-entry copper-silver ionisation system in eradication Legionella pneumophila in a tropical tertiary care hospital: implications for hospitals contaminated with Legionella in both hot and cold water.” J Hosp Infect. 2008 Feb;68(2):152-8