APA (7th ed.) Citation

Heinlein, R. A., & Robinson, S. (2007). Variable star. Blackstone Audio.

Chicago Style (17th ed.) Citation

Heinlein, Robert A., and Spider Robinson. Variable Star. Ashland, Or.: Blackstone Audio, 2007.

MLA (8th ed.) Citation

Heinlein, Robert A., and Spider Robinson. Variable Star. Blackstone Audio, 2007.

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