Blaabjerg , O. ., Elg , P. ., Gerhardt , W. ., Hellsing , K. ., Olafsdottir , E. ., Penttilä , I. ., … Uldall , A. . (1993). 6.2.4 A Nordic Reference Serum Suitable for Use as Trueness Control in the Clinical Routine Laboratory. Upsala Journal of Medical Sciences, 98(3), 405–412. https://doi.org/10.3109/03009739309179340