APA (7th ed.) Citation

Kay, L., Palen, S. E., Smith, B., & Blumenthal, G. 21st century astronomy : stars and galaxies: Stars and galaxies (Fourth edition.).

Chicago Style (17th ed.) Citation

Kay, Laura, Stacy E. Palen, Brad Smith, and George Blumenthal. 21st Century Astronomy : Stars and Galaxies: Stars and Galaxies. Fourth edition.

MLA (9th ed.) Citation

Kay, Laura, et al. 21st Century Astronomy : Stars and Galaxies: Stars and Galaxies. Fourth edition.

Warning: These citations may not always be 100% accurate.