Production and certification of secondary enzyme reference materials (ERMs). II: The need for meaningful protocols that assure photometric accuracy and a well-defined process for value assignmentKOEDAM, J. C; VAN DREUMEL, H. J; HAM, W. V. D et al.Clinical chemistry (Baltimore, Md.). 1986, Vol 32, Num 10, pp 1906-1913, issn 0009-9147Article

Production and certification of secondary enzyme reference materials (ERMs). I: Preparation of the sera and some of their propertiesKOEDAM, J. C; STEENTJES, G. M; BUITENHUIS, S et al.Clinical chemistry (Baltimore, Md.). 1986, Vol 32, Num 10, pp 1901-1905, issn 0009-9147Article

Primary human aspartate aminotransferase reference material. The catalytic activity concentration of AST in RM 8430 as measured by the IFCC reference method for AST in 10 enzyme standardization laboratoriesBOWERS, G. N. JR; MCCOMB, R. B; KOEDAM, J. C et al.Clinical chemistry (Baltimore, Md.). 1988, Vol 34, Num 2, pp 450-459, issn 0009-9147Article