Citazione Stile APA (7a Edizione)

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

Citazione stile Chigago Style (17a edizione)

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

Citatione MLA (8a ed.)

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