Dyfyniad APA

Gardner, M., & Schroeder, T. (1997). Puzzling questions about the solar system. Dover Publications.

Dyfyniad Arddull Chicago

Gardner, Martin, and Ted Schroeder. Puzzling Questions About the Solar System. Mineola, N.Y.: Dover Publications, 1997.

Dyfyniad MLA

Gardner, Martin, and Ted Schroeder. Puzzling Questions About the Solar System. Dover Publications, 1997.

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