C. Saelim, J. Opanuraks, C. Boonla, M. Patchsung, and P. Tosukhowong, “Elevated Urinary Iron, Zinc and Nickel Associate with Increased Oxidative Stress in Bladder Cancer Patients”, Insight Urol, vol. 31, no. 1, pp. 52–62, Jun. 2010.