Bulgaria: National Statistical Institute
Official government site offers information about the law on statistics, and information about the population, ecology, and economy of the country.
Republic of Bulgaria
Official government site tells about the government and the country in general. Includes the history of the country, some basic statistics, national symbols, public holidays, and a map of the districts as well as speeches by the prime minister and other government news and decrees.
US Library of Congress. Country Profile: Bulgaria
Overview of life, history, and culture of Bulgaria by the US Library of Congress.