1. Vinča Institute of Nuclear Sciences; University of Belgrade; P.O. Box 522 Belgrade 11001 Serbia
2. Faculty of Technology and Metallurgy; University of Belgrade; P.O. Box 35-08 Belgrade 11120 Serbia
3. Institute of Microbiology; Military Medical Academy; P.O. Box 33-55 Belgrade 11040 Serbia
4. Clinic for Endocrinology; Diabetes, and Metabolic Diseases, Faculty of Medicine, University of Belgrade; P. O. Box 497 Belgrade 11000 Serbia