Urinary creatinine concentrations in the U.S. population: implications for urinary biologic monitoring measurements.
Barr DB, Wilder LC, Caudill SP, Gonzalez AJ, Needham LL, Pirkle JL. Urinary creatinine concentrations in the U.S. population: implications for urinary biologic monitoring measurements. Environ Health Perspect. 2005 Feb; 113(2):192-200.