National Foreign Assessment Center (U.S.). (1980). USSR, coal industry problems and prospects. Central Intelligence Agency, National Foreign Assessment Center.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNational Foreign Assessment Center (U.S.). USSR, Coal Industry Problems and Prospects. Washington, D.C.: Central Intelligence Agency, National Foreign Assessment Center, 1980.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNational Foreign Assessment Center (U.S.). USSR, Coal Industry Problems and Prospects. Central Intelligence Agency, National Foreign Assessment Center, 1980.
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