Seeds, M. A. (1990). Foundations of astronomy (1990 edition.). Wadsworth Publishing Company.
Dyfyniad Arddull ChicagoSeeds, Michael A. Foundations of Astronomy. 1990 edition. Belmont, California: Wadsworth Publishing Company, 1990.
Dyfyniad MLASeeds, Michael A. Foundations of Astronomy. 1990 edition. Wadsworth Publishing Company, 1990.
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