Cita APA

Hester, J. (2007). 21st Century Astronomy Stars and Galaxies. McGraw Hill Companies Inc.

Chicago Style Citation

Hester, Jeff. 21st Century Astronomy Stars and Galaxies. McGraw Hill Companies Inc, 2007.

Cita MLA

Hester, Jeff. 21st Century Astronomy Stars and Galaxies. McGraw Hill Companies Inc, 2007.

Atenció: Aquestes cites poden no estar 100% correctes.