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Lua i Stíl Chicago (17ú heag.)Pryde, Philip Rust. Natural Resource Management and Conservation in the Soviet Union. Ann Arbor: University Microfilms International, 1969.
Lua MLA (9ú heag.)Pryde, Philip Rust. Natural Resource Management and Conservation in the Soviet Union. University Microfilms International, 1969.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.