APA (7th ed.) Zitazioa

(1971). U.S. foreign trade statistics: Classifications and cross-classifications, 1970.

Chicago Style (17th ed.) Zitazioa

U.S. Foreign Trade Statistics: Classifications and Cross-classifications, 1970. 1971.

MLA (9th ed.) Zitazioa

U.S. Foreign Trade Statistics: Classifications and Cross-classifications, 1970. 1971.

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