Não informado. (1971). Petroleum Refining and Petrochemicals Literature Abstracts. American Petroleum Institute.
Chicago-viite (17. p.)Não informado. Petroleum Refining and Petrochemicals Literature Abstracts. New York: American Petroleum Institute, 1971.
MLA-viite (8. p.)Não informado. Petroleum Refining and Petrochemicals Literature Abstracts. American Petroleum Institute, 1971.
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