APA (7th ed.) Citation

Protheroe, W. M., Capriotti, E. R., & Newsom, G. H. (1979). Exploring the universe. Merrill.

Chicago Style (17th ed.) Citation

Protheroe, W. M., E. R. Capriotti, and G. H. Newsom. Exploring the Universe. Columbus, OH: Merrill, 1979.

MLA (9th ed.) Citation

Protheroe, W. M., et al. Exploring the Universe. Merrill, 1979.