. . " United States Holocaust Memorial Museum http://collections.ushmm.org/search/catalog/irn514499"@en . "From the T︠S︡entralen dŭrzhaven arkhiv (Central State Archives), Bulgaria, Fond 453, Opis 2. "@en . . . . . . "Contains census of 1934 and other statistical data related to the occupation, social situation, age, nationality, religion, language and literacy of Bulgarians. Includes a special census by population for new territories."@en . . "The Main Directorate of Statistics was created in 1897, replacing earlier statistical offices. In 1953 it was replaced by the Central Statistical Admnistration. "@en . . "фонд 453К" . . "Главна дирекция на статистиката "@en . . "3 microfilm reels 35 mm"@en . .