1. Barltrop, D., Smith, A.: Interaction of lead with erythrocytes. Experientia (Basel) 27, 92?93 (1971)
2. Barth, D. S.: In: Environmental health aspects of lead, Commission of the European Communities and U.S. Environmental Protection Agency, eds., p. 909. Luxembourg: Grand Duché 1973
3. Berlin, A., Schauer, K. H., Smeets, J.: Standardisation of ALA-D determination at the European level; intercalibration and applications. Communication No. 119 presentend at the ?International Symposium on Recent Advances in the Assessment of the Health Effects of Environmental Pollution? organized jointly by CEC-EPA-WHO, Paris, June 24?28, 1974
4. Bruenger, F. W., Stevens, W., Stover, B. J.: The association of 210Pb with constituents of erythrocytes. Health Physics 25, 37?42 (1973)
5. Buchet, J. P., Lauwerys, R. R.: Working document No. 3414/73e submitted for the ?Technical seminar on the measurement of delta-aminolevulinic acid dehydratase in blood using a ?standardized? European method?, Erlangen, September 24?28, 1973, edited by the Commission of the European Communities, Health Protection Directorate. Luxembourg: Grand Duché 1973