Lange , O. (1969). Theory of Reproduction and Accumulation. PWN.
Lua i Stíl Chicago (17ú heag.)Lange , Oskar. Theory of Reproduction and Accumulation. Warsaw: PWN, 1969.
Lua MLA (9ú heag.)Lange , Oskar. Theory of Reproduction and Accumulation. PWN, 1969.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.