Παραπομπή APA

Walls, L. D. (2009). The passage to Cosmos: Alexander von Humboldt and the shaping of America. Chicago: The University of Chicago Press.

Παραπομπή Chicago Style

Walls, Laura Dassow. The Passage to Cosmos: Alexander Von Humboldt and the Shaping of America. Chicago: The University of Chicago Press, 2009.

Παραπομπή MLA

Walls, Laura Dassow. The Passage to Cosmos: Alexander Von Humboldt and the Shaping of America. Chicago: The University of Chicago Press, 2009.

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