Dyfyniad APA

Ryden, B. S. (2014). Introduction to cosmology (Pearson new international edition.). Pearson.

Dyfyniad Arddull Chicago

Ryden, Barbara Sue. Introduction to Cosmology. Pearson new international edition. Harlow: Pearson, 2014.

Dyfyniad MLA

Ryden, Barbara Sue. Introduction to Cosmology. Pearson new international edition. Pearson, 2014.

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