Lange.Oskar. (1971). POLITICAL ECONOMY: PWN- POLISH SCIENTIFIC PUBLISHERS. WARSZAWA.
Citace podle Chicago (17th ed.)Lange.Oskar. POLITICAL ECONOMY: PWN- POLISH SCIENTIFIC PUBLISHERS. panstwowe wydawnictwo naukowe: WARSZAWA, 1971.
Citace podle MLA (9th ed.)Lange.Oskar. POLITICAL ECONOMY: PWN- POLISH SCIENTIFIC PUBLISHERS. WARSZAWA, 1971.