Dyfyniad APA

Bless, R. C. (2013). Discovering the cosmos (2nd ed.). University Science Books.

Dyfyniad Arddull Chicago

Bless, Robert C. Discovering the Cosmos. 2nd ed. Mill Valley, Calif.: University Science Books, 2013.

Dyfyniad MLA

Bless, Robert C. Discovering the Cosmos. 2nd ed. University Science Books, 2013.

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