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2. Renal concentration tests
3. 3. AV. Wolf, Aqueous Solutions and Body Fluids . New York, NY: Harper and Row; 1966 :28 -31 , 28 -31 , 28 -31 .
4. 5. RA. Pesalk The Evolution of the Abbe RefractometerAvailable at: http://www.humboldt.edu/~scimus/essays/EvolAbbeRef/EvolAbbeRef.htm. Accessed Aug 16, 2001