Dyfyniad APA

ebrary, Inc. (2005). Polar icebreaker roles and U.S. future needs: A preliminary assessment. National Academy Press.

Dyfyniad Arddull Chicago

ebrary, Inc. Polar Icebreaker Roles and U.S. Future Needs: A Preliminary Assessment. Washington, D.C.: National Academy Press, 2005.

Dyfyniad MLA

ebrary, Inc. Polar Icebreaker Roles and U.S. Future Needs: A Preliminary Assessment. National Academy Press, 2005.

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