- Author: Encyclopaedia Britannica IncAnthony Green
- Language: English
- Year: 2010
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2010
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2009
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2010
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2009
- Author: Encyclopaedia Britannica
- Language: English
- Year: 2010
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2008
- Author: Encyclopaedia Britannica Inc.
- Language: English
- Year: 2010
- Author: Encyclopedia Britannica Editorial Encyclopedia Britannica Editorial
- Language: English
- Year: 2008