Factors influencing between-laboratory variability of C-reactive protein results as evidenced by the Belgian External Quality Assessment(EQA) Scheme29, Devleeschouwer, N., Libeer J.C., Chapelle J.P., Struway C.L., Gyssels C., L'Hoir A., and Albert A. , Scand.J.Clin.Lab Invest, 0/10/1994, Volume 54, Issue 6, Number 440, p.435 - 440, (1994)