Series of two postage stamps and a special postmark on the theme “Bulgarian scientists: 125 years since the birth of Acad. Nikola Obreshkov and 125 years since the birth of Acad. Georgi Nadjakov” will be presented on 16 December at 11:00 at the Bulgarian Academy of Sciences /1, 15 November Str./. The painter of the stamps is Assoc. Prof. Stoyan Dechev.

The event will be attended by the Vice-Presidents of BAS Corr. Mem. Evdokia Pasheva and Corr. Mem. Stefan Hadjitodorov, the CEO of “Bulgarian Posts” Deyan Daneshki, the Directors of the Institute of Solid State Physics and the Institute of Mathematics and Informatics Prof. Hassan Chamati and Prof. Peter Boyvalenkov.

Acad. Nadjakov is the discoverer of the photoelectric state of matter (1937) which is the basis of modern copying technology, memory storage devices, X-ray dosimeters, satellite images and television technology without vacuum tubes. His discovery was officially recognized and registered as scientific discovery No. 1 for Bulgaria on 12 March 1981. He made a significant contribution to the development of higher education and scientific activity in physics in Bulgaria.

Acad. Nikola Obreshkov is a scientist-mathematician of world renown and recognition. His scientific heritage includes 250 publications in national and foreign scientific journals and publications – including textbooks and several monographs. His scientific interests include: classical algebra, analysis, probability theory and mathematical statistics, integral geometry, topology, mechanics, equations of mathematical physics, number theory.

The two stamps will be put on sale on 16.12.2021, after 12:00 in the building of the Central Post Office, Sofia, 6, Gurko Str.