LAZARCIK, Gregor. Bulgarian Agricultural Production, Output, Expenses, Gross and Net Product, and Productivity, at 1968 Prices, 1939 and 1948-1970. 1. ed. New York : Economic Studies Riverside Research Institute, 1973. 61 s. Occasional Papers of the Research Project on National Income in East Central Europe, 39. [Copy count : 1, currently available 1, at library only 0]