- Author: Helize van Vuuren
- Language: English
- Year: 2016
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- Year: 2010
- Author: David Attwell
- Language: English
- Year: 2006
- Author: Michael Chapman
- Language: English
- Year: 2008
- Author: Heywood Christopher
- Language: English
- Year: 2011
- Author: Van der Vlies Andrew
- Language: English
- Year: 2017