Dyfyniad APA

Freedman, R. A. (2005). Universe: The Solar system (student). New York: W. H. Freeman and Company.

Dyfyniad Arddull Chicago

Freedman, Roger A. Universe: The Solar System (student). New York: W. H. Freeman and Company, 2005.

Dyfyniad MLA

Freedman, Roger A. Universe: The Solar System (student). New York: W. H. Freeman and Company, 2005.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.