Bulgarian National Day was celebrated on 9th September, the 21st anniversary of the Socialist Revolution in Bulgaria, with a military parade and demonstreation on the 9th September Square, Sofia, capital of Bulgaria Taking the salute on the tribune of the Georgi Dimitrov Mausoleum during the demonstration are seen left to right: General Ivan Mihailov, Deputy Prime Minister Todor Zhivkov, Prime Minister and First Secretary of the Bulgarian Communist Party, and Georgi Traikov, Chairman of the Presidium of the National Assembly