APA Citation

 Marshak, S. (2012).  Earth: Portrait of a planet.  W. W. Norton.

Chicago Style Citation

 Marshak, Stephen.  Earth: Portrait of a Planet.  W. W. Norton, 2012.

MLA Citation

 Marshak, Stephen.  Earth: Portrait of a Planet.  W. W. Norton, 2012.

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