1. Dehkordi F. G. “The Effect of Heavy Metals on the Performance of Rotating Biological Contactors ” thesis presented to Oklahoma Univ. at Stillwater OK in 1980 in partial fulfillment of the requirements for the degree of Master of Science.
2. Gellman I. “The Toxicity of Metals Upon the Activated Sludge Process ” thesis presented to Rutgers Univ. at New Brunswick NJ in partial fulfillment of the requirements for the degree of Master of Science.